1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011, 2012
4 Free Software Foundation, Inc.
5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
6 Rewritten by Jason Merrill (jason@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
38 #include "c-family/c-common.h"
39 #include "c-family/c-objc.h"
40 #include "cp-objcp-common.h"
41 #include "tree-inline.h"
46 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work. */
56 struct GTY ((chain_next ("%h.next"))) pending_template {
57 struct pending_template *next;
58 struct tinst_level *tinst;
61 static GTY(()) struct pending_template *pending_templates;
62 static GTY(()) struct pending_template *last_pending_template;
64 int processing_template_parmlist;
65 static int template_header_count;
67 static GTY(()) tree saved_trees;
68 static VEC(int,heap) *inline_parm_levels;
70 static GTY(()) struct tinst_level *current_tinst_level;
72 static GTY(()) tree saved_access_scope;
74 /* Live only within one (recursive) call to tsubst_expr. We use
75 this to pass the statement expression node from the STMT_EXPR
76 to the EXPR_STMT that is its result. */
77 static tree cur_stmt_expr;
79 /* A map from local variable declarations in the body of the template
80 presently being instantiated to the corresponding instantiated
82 static htab_t local_specializations;
84 typedef struct GTY(()) spec_entry
91 static GTY ((param_is (spec_entry)))
92 htab_t decl_specializations;
94 static GTY ((param_is (spec_entry)))
95 htab_t type_specializations;
97 /* Contains canonical template parameter types. The vector is indexed by
98 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
99 TREE_LIST, whose TREE_VALUEs contain the canonical template
100 parameters of various types and levels. */
101 static GTY(()) VEC(tree,gc) *canonical_template_parms;
103 #define UNIFY_ALLOW_NONE 0
104 #define UNIFY_ALLOW_MORE_CV_QUAL 1
105 #define UNIFY_ALLOW_LESS_CV_QUAL 2
106 #define UNIFY_ALLOW_DERIVED 4
107 #define UNIFY_ALLOW_INTEGER 8
108 #define UNIFY_ALLOW_OUTER_LEVEL 16
109 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
110 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
112 enum template_base_result {
114 tbr_ambiguous_baseclass,
118 static void push_access_scope (tree);
119 static void pop_access_scope (tree);
120 static void push_deduction_access_scope (tree);
121 static void pop_deduction_access_scope (tree);
122 static bool resolve_overloaded_unification (tree, tree, tree, tree,
123 unification_kind_t, int,
125 static int try_one_overload (tree, tree, tree, tree, tree,
126 unification_kind_t, int, bool, bool);
127 static int unify (tree, tree, tree, tree, int, bool);
128 static void add_pending_template (tree);
129 static tree reopen_tinst_level (struct tinst_level *);
130 static tree tsubst_initializer_list (tree, tree);
131 static tree get_class_bindings (tree, tree, tree);
132 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
134 static void tsubst_enum (tree, tree, tree);
135 static tree add_to_template_args (tree, tree);
136 static tree add_outermost_template_args (tree, tree);
137 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
138 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
140 static int type_unification_real (tree, tree, tree, const tree *,
141 unsigned int, int, unification_kind_t, int,
143 static void note_template_header (int);
144 static tree convert_nontype_argument_function (tree, tree);
145 static tree convert_nontype_argument (tree, tree, tsubst_flags_t);
146 static tree convert_template_argument (tree, tree, tree,
147 tsubst_flags_t, int, tree);
148 static int for_each_template_parm (tree, tree_fn_t, void*,
149 struct pointer_set_t*, bool);
150 static tree expand_template_argument_pack (tree);
151 static tree build_template_parm_index (int, int, int, int, tree, tree);
152 static bool inline_needs_template_parms (tree);
153 static void push_inline_template_parms_recursive (tree, int);
154 static tree retrieve_local_specialization (tree);
155 static void register_local_specialization (tree, tree);
156 static hashval_t hash_specialization (const void *p);
157 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
158 static int mark_template_parm (tree, void *);
159 static int template_parm_this_level_p (tree, void *);
160 static tree tsubst_friend_function (tree, tree);
161 static tree tsubst_friend_class (tree, tree);
162 static int can_complete_type_without_circularity (tree);
163 static tree get_bindings (tree, tree, tree, bool);
164 static int template_decl_level (tree);
165 static int check_cv_quals_for_unify (int, tree, tree);
166 static void template_parm_level_and_index (tree, int*, int*);
167 static int unify_pack_expansion (tree, tree, tree,
168 tree, unification_kind_t, bool, bool);
169 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
170 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
171 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
172 static void regenerate_decl_from_template (tree, tree);
173 static tree most_specialized_class (tree, tree, tsubst_flags_t);
174 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
175 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
176 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
177 static bool check_specialization_scope (void);
178 static tree process_partial_specialization (tree);
179 static void set_current_access_from_decl (tree);
180 static enum template_base_result get_template_base (tree, tree, tree, tree,
182 static tree try_class_unification (tree, tree, tree, tree, bool);
183 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
185 static bool template_template_parm_bindings_ok_p (tree, tree);
186 static int template_args_equal (tree, tree);
187 static void tsubst_default_arguments (tree);
188 static tree for_each_template_parm_r (tree *, int *, void *);
189 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
190 static void copy_default_args_to_explicit_spec (tree);
191 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
192 static int eq_local_specializations (const void *, const void *);
193 static bool dependent_template_arg_p (tree);
194 static bool any_template_arguments_need_structural_equality_p (tree);
195 static bool dependent_type_p_r (tree);
196 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
197 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
198 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
199 static tree tsubst_decl (tree, tree, tsubst_flags_t);
200 static void perform_typedefs_access_check (tree tmpl, tree targs);
201 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
203 static tree listify (tree);
204 static tree listify_autos (tree, tree);
205 static tree template_parm_to_arg (tree t);
206 static bool arg_from_parm_pack_p (tree, tree);
207 static tree current_template_args (void);
208 static tree fixup_template_type_parm_type (tree, int);
209 static tree fixup_template_parm_index (tree, tree, int);
210 static tree tsubst_template_parm (tree, tree, tsubst_flags_t);
212 /* Make the current scope suitable for access checking when we are
213 processing T. T can be FUNCTION_DECL for instantiated function
214 template, or VAR_DECL for static member variable (need by
215 instantiate_decl). */
218 push_access_scope (tree t)
220 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
221 || TREE_CODE (t) == VAR_DECL);
223 if (DECL_FRIEND_CONTEXT (t))
224 push_nested_class (DECL_FRIEND_CONTEXT (t));
225 else if (DECL_CLASS_SCOPE_P (t))
226 push_nested_class (DECL_CONTEXT (t));
228 push_to_top_level ();
230 if (TREE_CODE (t) == FUNCTION_DECL)
232 saved_access_scope = tree_cons
233 (NULL_TREE, current_function_decl, saved_access_scope);
234 current_function_decl = t;
238 /* Restore the scope set up by push_access_scope. T is the node we
242 pop_access_scope (tree t)
244 if (TREE_CODE (t) == FUNCTION_DECL)
246 current_function_decl = TREE_VALUE (saved_access_scope);
247 saved_access_scope = TREE_CHAIN (saved_access_scope);
250 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
253 pop_from_top_level ();
256 /* Do any processing required when DECL (a member template
257 declaration) is finished. Returns the TEMPLATE_DECL corresponding
258 to DECL, unless it is a specialization, in which case the DECL
259 itself is returned. */
262 finish_member_template_decl (tree decl)
264 if (decl == error_mark_node)
265 return error_mark_node;
267 gcc_assert (DECL_P (decl));
269 if (TREE_CODE (decl) == TYPE_DECL)
273 type = TREE_TYPE (decl);
274 if (type == error_mark_node)
275 return error_mark_node;
276 if (MAYBE_CLASS_TYPE_P (type)
277 && CLASSTYPE_TEMPLATE_INFO (type)
278 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
280 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
281 check_member_template (tmpl);
286 else if (TREE_CODE (decl) == FIELD_DECL)
287 error ("data member %qD cannot be a member template", decl);
288 else if (DECL_TEMPLATE_INFO (decl))
290 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
292 check_member_template (DECL_TI_TEMPLATE (decl));
293 return DECL_TI_TEMPLATE (decl);
299 error ("invalid member template declaration %qD", decl);
301 return error_mark_node;
304 /* Create a template info node. */
307 build_template_info (tree template_decl, tree template_args)
309 tree result = make_node (TEMPLATE_INFO);
310 TI_TEMPLATE (result) = template_decl;
311 TI_ARGS (result) = template_args;
315 /* Return the template info node corresponding to T, whatever T is. */
318 get_template_info (const_tree t)
320 tree tinfo = NULL_TREE;
322 if (!t || t == error_mark_node)
325 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
326 tinfo = DECL_TEMPLATE_INFO (t);
328 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
331 if (TAGGED_TYPE_P (t))
332 tinfo = TYPE_TEMPLATE_INFO (t);
333 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
334 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
339 /* Returns the template nesting level of the indicated class TYPE.
349 A<T>::B<U> has depth two, while A<T> has depth one.
350 Both A<T>::B<int> and A<int>::B<U> have depth one, if
351 they are instantiations, not specializations.
353 This function is guaranteed to return 0 if passed NULL_TREE so
354 that, for example, `template_class_depth (current_class_type)' is
358 template_class_depth (tree type)
363 type && TREE_CODE (type) != NAMESPACE_DECL;
364 type = (TREE_CODE (type) == FUNCTION_DECL)
365 ? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type))
367 tree tinfo = get_template_info (type);
369 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
370 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
377 /* Subroutine of maybe_begin_member_template_processing.
378 Returns true if processing DECL needs us to push template parms. */
381 inline_needs_template_parms (tree decl)
383 if (! DECL_TEMPLATE_INFO (decl))
386 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
387 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
390 /* Subroutine of maybe_begin_member_template_processing.
391 Push the template parms in PARMS, starting from LEVELS steps into the
392 chain, and ending at the beginning, since template parms are listed
396 push_inline_template_parms_recursive (tree parmlist, int levels)
398 tree parms = TREE_VALUE (parmlist);
402 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
404 ++processing_template_decl;
405 current_template_parms
406 = tree_cons (size_int (processing_template_decl),
407 parms, current_template_parms);
408 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
410 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
412 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
414 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
416 if (parm == error_mark_node)
419 gcc_assert (DECL_P (parm));
421 switch (TREE_CODE (parm))
430 /* Make a CONST_DECL as is done in process_template_parm.
431 It is ugly that we recreate this here; the original
432 version built in process_template_parm is no longer
434 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
435 CONST_DECL, DECL_NAME (parm),
437 DECL_ARTIFICIAL (decl) = 1;
438 TREE_CONSTANT (decl) = 1;
439 TREE_READONLY (decl) = 1;
440 DECL_INITIAL (decl) = DECL_INITIAL (parm);
441 SET_DECL_TEMPLATE_PARM_P (decl);
452 /* Restore the template parameter context for a member template or
453 a friend template defined in a class definition. */
456 maybe_begin_member_template_processing (tree decl)
461 if (inline_needs_template_parms (decl))
463 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
464 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
466 if (DECL_TEMPLATE_SPECIALIZATION (decl))
469 parms = TREE_CHAIN (parms);
472 push_inline_template_parms_recursive (parms, levels);
475 /* Remember how many levels of template parameters we pushed so that
476 we can pop them later. */
477 VEC_safe_push (int, heap, inline_parm_levels, levels);
480 /* Undo the effects of maybe_begin_member_template_processing. */
483 maybe_end_member_template_processing (void)
488 if (VEC_length (int, inline_parm_levels) == 0)
491 last = VEC_pop (int, inline_parm_levels);
492 for (i = 0; i < last; ++i)
494 --processing_template_decl;
495 current_template_parms = TREE_CHAIN (current_template_parms);
500 /* Return a new template argument vector which contains all of ARGS,
501 but has as its innermost set of arguments the EXTRA_ARGS. */
504 add_to_template_args (tree args, tree extra_args)
511 if (args == NULL_TREE || extra_args == error_mark_node)
514 extra_depth = TMPL_ARGS_DEPTH (extra_args);
515 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
517 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
518 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
520 for (j = 1; j <= extra_depth; ++j, ++i)
521 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
526 /* Like add_to_template_args, but only the outermost ARGS are added to
527 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
528 (EXTRA_ARGS) levels are added. This function is used to combine
529 the template arguments from a partial instantiation with the
530 template arguments used to attain the full instantiation from the
531 partial instantiation. */
534 add_outermost_template_args (tree args, tree extra_args)
538 /* If there are more levels of EXTRA_ARGS than there are ARGS,
539 something very fishy is going on. */
540 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
542 /* If *all* the new arguments will be the EXTRA_ARGS, just return
544 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
547 /* For the moment, we make ARGS look like it contains fewer levels. */
548 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
550 new_args = add_to_template_args (args, extra_args);
552 /* Now, we restore ARGS to its full dimensions. */
553 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
558 /* Return the N levels of innermost template arguments from the ARGS. */
561 get_innermost_template_args (tree args, int n)
569 /* If N is 1, just return the innermost set of template arguments. */
571 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
573 /* If we're not removing anything, just return the arguments we were
575 extra_levels = TMPL_ARGS_DEPTH (args) - n;
576 gcc_assert (extra_levels >= 0);
577 if (extra_levels == 0)
580 /* Make a new set of arguments, not containing the outer arguments. */
581 new_args = make_tree_vec (n);
582 for (i = 1; i <= n; ++i)
583 SET_TMPL_ARGS_LEVEL (new_args, i,
584 TMPL_ARGS_LEVEL (args, i + extra_levels));
589 /* The inverse of get_innermost_template_args: Return all but the innermost
590 EXTRA_LEVELS levels of template arguments from the ARGS. */
593 strip_innermost_template_args (tree args, int extra_levels)
596 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
601 /* If N is 1, just return the outermost set of template arguments. */
603 return TMPL_ARGS_LEVEL (args, 1);
605 /* If we're not removing anything, just return the arguments we were
607 gcc_assert (extra_levels >= 0);
608 if (extra_levels == 0)
611 /* Make a new set of arguments, not containing the inner arguments. */
612 new_args = make_tree_vec (n);
613 for (i = 1; i <= n; ++i)
614 SET_TMPL_ARGS_LEVEL (new_args, i,
615 TMPL_ARGS_LEVEL (args, i));
620 /* We've got a template header coming up; push to a new level for storing
624 begin_template_parm_list (void)
626 /* We use a non-tag-transparent scope here, which causes pushtag to
627 put tags in this scope, rather than in the enclosing class or
628 namespace scope. This is the right thing, since we want
629 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
630 global template class, push_template_decl handles putting the
631 TEMPLATE_DECL into top-level scope. For a nested template class,
634 template <class T> struct S1 {
635 template <class T> struct S2 {};
638 pushtag contains special code to call pushdecl_with_scope on the
639 TEMPLATE_DECL for S2. */
640 begin_scope (sk_template_parms, NULL);
641 ++processing_template_decl;
642 ++processing_template_parmlist;
643 note_template_header (0);
646 /* This routine is called when a specialization is declared. If it is
647 invalid to declare a specialization here, an error is reported and
648 false is returned, otherwise this routine will return true. */
651 check_specialization_scope (void)
653 tree scope = current_scope ();
657 An explicit specialization shall be declared in the namespace of
658 which the template is a member, or, for member templates, in the
659 namespace of which the enclosing class or enclosing class
660 template is a member. An explicit specialization of a member
661 function, member class or static data member of a class template
662 shall be declared in the namespace of which the class template
664 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
666 error ("explicit specialization in non-namespace scope %qD", scope);
672 In an explicit specialization declaration for a member of a class
673 template or a member template that appears in namespace scope,
674 the member template and some of its enclosing class templates may
675 remain unspecialized, except that the declaration shall not
676 explicitly specialize a class member template if its enclosing
677 class templates are not explicitly specialized as well. */
678 if (current_template_parms)
680 error ("enclosing class templates are not explicitly specialized");
687 /* We've just seen template <>. */
690 begin_specialization (void)
692 begin_scope (sk_template_spec, NULL);
693 note_template_header (1);
694 return check_specialization_scope ();
697 /* Called at then end of processing a declaration preceded by
701 end_specialization (void)
704 reset_specialization ();
707 /* Any template <>'s that we have seen thus far are not referring to a
708 function specialization. */
711 reset_specialization (void)
713 processing_specialization = 0;
714 template_header_count = 0;
717 /* We've just seen a template header. If SPECIALIZATION is nonzero,
718 it was of the form template <>. */
721 note_template_header (int specialization)
723 processing_specialization = specialization;
724 template_header_count++;
727 /* We're beginning an explicit instantiation. */
730 begin_explicit_instantiation (void)
732 gcc_assert (!processing_explicit_instantiation);
733 processing_explicit_instantiation = true;
738 end_explicit_instantiation (void)
740 gcc_assert (processing_explicit_instantiation);
741 processing_explicit_instantiation = false;
744 /* An explicit specialization or partial specialization TMPL is being
745 declared. Check that the namespace in which the specialization is
746 occurring is permissible. Returns false iff it is invalid to
747 specialize TMPL in the current namespace. */
750 check_specialization_namespace (tree tmpl)
752 tree tpl_ns = decl_namespace_context (tmpl);
756 An explicit specialization shall be declared in the namespace of
757 which the template is a member, or, for member templates, in the
758 namespace of which the enclosing class or enclosing class
759 template is a member. An explicit specialization of a member
760 function, member class or static data member of a class template
761 shall be declared in the namespace of which the class template is
763 if (current_scope() != DECL_CONTEXT (tmpl)
764 && !at_namespace_scope_p ())
766 error ("specialization of %qD must appear at namespace scope", tmpl);
769 if (is_associated_namespace (current_namespace, tpl_ns))
770 /* Same or super-using namespace. */
774 permerror (input_location, "specialization of %qD in different namespace", tmpl);
775 permerror (input_location, " from definition of %q+#D", tmpl);
780 /* SPEC is an explicit instantiation. Check that it is valid to
781 perform this explicit instantiation in the current namespace. */
784 check_explicit_instantiation_namespace (tree spec)
788 /* DR 275: An explicit instantiation shall appear in an enclosing
789 namespace of its template. */
790 ns = decl_namespace_context (spec);
791 if (!is_ancestor (current_namespace, ns))
792 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
793 "(which does not enclose namespace %qD)",
794 spec, current_namespace, ns);
797 /* The TYPE is being declared. If it is a template type, that means it
798 is a partial specialization. Do appropriate error-checking. */
801 maybe_process_partial_specialization (tree type)
805 if (type == error_mark_node)
806 return error_mark_node;
808 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
810 error ("name of class shadows template template parameter %qD",
812 return error_mark_node;
815 context = TYPE_CONTEXT (type);
817 if ((CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
818 /* Consider non-class instantiations of alias templates as
821 && TYPE_TEMPLATE_INFO (type)
822 && DECL_LANG_SPECIFIC (TYPE_NAME (type))
823 && DECL_USE_TEMPLATE (TYPE_NAME (type))))
825 /* This is for ordinary explicit specialization and partial
826 specialization of a template class such as:
828 template <> class C<int>;
832 template <class T> class C<T*>;
834 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
836 if (CLASS_TYPE_P (type)
837 && CLASSTYPE_IMPLICIT_INSTANTIATION (type)
838 && !COMPLETE_TYPE_P (type))
840 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
841 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
842 if (processing_template_decl)
844 if (push_template_decl (TYPE_MAIN_DECL (type))
846 return error_mark_node;
849 else if (CLASS_TYPE_P (type)
850 && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
851 error ("specialization of %qT after instantiation", type);
853 if (DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (type)))
855 error ("partial specialization of alias template %qD",
856 TYPE_TI_TEMPLATE (type));
857 return error_mark_node;
860 else if (CLASS_TYPE_P (type)
861 && !CLASSTYPE_USE_TEMPLATE (type)
862 && CLASSTYPE_TEMPLATE_INFO (type)
863 && context && CLASS_TYPE_P (context)
864 && CLASSTYPE_TEMPLATE_INFO (context))
866 /* This is for an explicit specialization of member class
867 template according to [temp.expl.spec/18]:
869 template <> template <class U> class C<int>::D;
871 The context `C<int>' must be an implicit instantiation.
872 Otherwise this is just a member class template declared
875 template <> class C<int> { template <class U> class D; };
876 template <> template <class U> class C<int>::D;
878 In the first case, `C<int>::D' is a specialization of `C<T>::D'
879 while in the second case, `C<int>::D' is a primary template
880 and `C<T>::D' may not exist. */
882 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
883 && !COMPLETE_TYPE_P (type))
886 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
888 if (current_namespace
889 != decl_namespace_context (tmpl))
891 permerror (input_location, "specializing %q#T in different namespace", type);
892 permerror (input_location, " from definition of %q+#D", tmpl);
895 /* Check for invalid specialization after instantiation:
897 template <> template <> class C<int>::D<int>;
898 template <> template <class U> class C<int>::D; */
900 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
901 t; t = TREE_CHAIN (t))
903 tree inst = TREE_VALUE (t);
904 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
906 /* We already have a full specialization of this partial
907 instantiation. Reassign it to the new member
908 specialization template. */
913 elt.tmpl = most_general_template (tmpl);
914 elt.args = CLASSTYPE_TI_ARGS (inst);
917 htab_remove_elt (type_specializations, &elt);
920 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
922 slot = htab_find_slot (type_specializations, &elt, INSERT);
923 entry = ggc_alloc_spec_entry ();
927 else if (COMPLETE_OR_OPEN_TYPE_P (inst))
928 /* But if we've had an implicit instantiation, that's a
929 problem ([temp.expl.spec]/6). */
930 error ("specialization %qT after instantiation %qT",
934 /* Mark TYPE as a specialization. And as a result, we only
935 have one level of template argument for the innermost
937 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
938 CLASSTYPE_TI_ARGS (type)
939 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
942 else if (processing_specialization)
944 /* Someday C++0x may allow for enum template specialization. */
945 if (cxx_dialect > cxx98 && TREE_CODE (type) == ENUMERAL_TYPE
946 && CLASS_TYPE_P (context) && CLASSTYPE_USE_TEMPLATE (context))
947 pedwarn (input_location, OPT_pedantic, "template specialization "
948 "of %qD not allowed by ISO C++", type);
951 error ("explicit specialization of non-template %qT", type);
952 return error_mark_node;
959 /* Returns nonzero if we can optimize the retrieval of specializations
960 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
961 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
964 optimize_specialization_lookup_p (tree tmpl)
966 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
967 && DECL_CLASS_SCOPE_P (tmpl)
968 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
970 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
971 /* The optimized lookup depends on the fact that the
972 template arguments for the member function template apply
973 purely to the containing class, which is not true if the
974 containing class is an explicit or partial
976 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
977 && !DECL_MEMBER_TEMPLATE_P (tmpl)
978 && !DECL_CONV_FN_P (tmpl)
979 /* It is possible to have a template that is not a member
980 template and is not a member of a template class:
982 template <typename T>
983 struct S { friend A::f(); };
985 Here, the friend function is a template, but the context does
986 not have template information. The optimized lookup relies
987 on having ARGS be the template arguments for both the class
988 and the function template. */
989 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
992 /* Retrieve the specialization (in the sense of [temp.spec] - a
993 specialization is either an instantiation or an explicit
994 specialization) of TMPL for the given template ARGS. If there is
995 no such specialization, return NULL_TREE. The ARGS are a vector of
996 arguments, or a vector of vectors of arguments, in the case of
997 templates with more than one level of parameters.
999 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
1000 then we search for a partial specialization matching ARGS. This
1001 parameter is ignored if TMPL is not a class template. */
1004 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
1006 if (args == error_mark_node)
1009 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1011 /* There should be as many levels of arguments as there are
1012 levels of parameters. */
1013 gcc_assert (TMPL_ARGS_DEPTH (args)
1014 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
1016 if (optimize_specialization_lookup_p (tmpl))
1018 tree class_template;
1019 tree class_specialization;
1020 VEC(tree,gc) *methods;
1024 /* The template arguments actually apply to the containing
1025 class. Find the class specialization with those
1027 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
1028 class_specialization
1029 = retrieve_specialization (class_template, args, 0);
1030 if (!class_specialization)
1032 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
1033 for the specialization. */
1034 idx = class_method_index_for_fn (class_specialization, tmpl);
1037 /* Iterate through the methods with the indicated name, looking
1038 for the one that has an instance of TMPL. */
1039 methods = CLASSTYPE_METHOD_VEC (class_specialization);
1040 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1042 tree fn = OVL_CURRENT (fns);
1043 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1044 /* using-declarations can add base methods to the method vec,
1045 and we don't want those here. */
1046 && DECL_CONTEXT (fn) == class_specialization)
1055 htab_t specializations;
1059 elt.spec = NULL_TREE;
1061 if (DECL_CLASS_TEMPLATE_P (tmpl))
1062 specializations = type_specializations;
1064 specializations = decl_specializations;
1067 hash = hash_specialization (&elt);
1068 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1076 /* Like retrieve_specialization, but for local declarations. */
1079 retrieve_local_specialization (tree tmpl)
1083 if (local_specializations == NULL)
1086 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1087 htab_hash_pointer (tmpl));
1088 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1091 /* Returns nonzero iff DECL is a specialization of TMPL. */
1094 is_specialization_of (tree decl, tree tmpl)
1098 if (TREE_CODE (decl) == FUNCTION_DECL)
1102 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1108 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1110 for (t = TREE_TYPE (decl);
1112 t = CLASSTYPE_USE_TEMPLATE (t)
1113 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1114 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1121 /* Returns nonzero iff DECL is a specialization of friend declaration
1122 FRIEND_DECL according to [temp.friend]. */
1125 is_specialization_of_friend (tree decl, tree friend_decl)
1127 bool need_template = true;
1130 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1131 || TREE_CODE (decl) == TYPE_DECL);
1133 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1134 of a template class, we want to check if DECL is a specialization
1136 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1137 && DECL_TEMPLATE_INFO (friend_decl)
1138 && !DECL_USE_TEMPLATE (friend_decl))
1140 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1141 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1142 need_template = false;
1144 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1145 && !PRIMARY_TEMPLATE_P (friend_decl))
1146 need_template = false;
1148 /* There is nothing to do if this is not a template friend. */
1149 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1152 if (is_specialization_of (decl, friend_decl))
1156 A member of a class template may be declared to be a friend of a
1157 non-template class. In this case, the corresponding member of
1158 every specialization of the class template is a friend of the
1159 class granting friendship.
1161 For example, given a template friend declaration
1163 template <class T> friend void A<T>::f();
1165 the member function below is considered a friend
1167 template <> struct A<int> {
1171 For this type of template friend, TEMPLATE_DEPTH below will be
1172 nonzero. To determine if DECL is a friend of FRIEND, we first
1173 check if the enclosing class is a specialization of another. */
1175 template_depth = template_class_depth (CP_DECL_CONTEXT (friend_decl));
1177 && DECL_CLASS_SCOPE_P (decl)
1178 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1179 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1181 /* Next, we check the members themselves. In order to handle
1182 a few tricky cases, such as when FRIEND_DECL's are
1184 template <class T> friend void A<T>::g(T t);
1185 template <class T> template <T t> friend void A<T>::h();
1189 void A<int>::g(int);
1190 template <int> void A<int>::h();
1192 we need to figure out ARGS, the template arguments from
1193 the context of DECL. This is required for template substitution
1194 of `T' in the function parameter of `g' and template parameter
1195 of `h' in the above examples. Here ARGS corresponds to `int'. */
1197 tree context = DECL_CONTEXT (decl);
1198 tree args = NULL_TREE;
1199 int current_depth = 0;
1201 while (current_depth < template_depth)
1203 if (CLASSTYPE_TEMPLATE_INFO (context))
1205 if (current_depth == 0)
1206 args = TYPE_TI_ARGS (context);
1208 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1211 context = TYPE_CONTEXT (context);
1214 if (TREE_CODE (decl) == FUNCTION_DECL)
1219 tree friend_args_type;
1220 tree decl_args_type;
1222 /* Make sure that both DECL and FRIEND_DECL are templates or
1224 is_template = DECL_TEMPLATE_INFO (decl)
1225 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1226 if (need_template ^ is_template)
1228 else if (is_template)
1230 /* If both are templates, check template parameter list. */
1232 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1234 if (!comp_template_parms
1235 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1239 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1242 decl_type = TREE_TYPE (decl);
1244 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1245 tf_none, NULL_TREE);
1246 if (friend_type == error_mark_node)
1249 /* Check if return types match. */
1250 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1253 /* Check if function parameter types match, ignoring the
1254 `this' parameter. */
1255 friend_args_type = TYPE_ARG_TYPES (friend_type);
1256 decl_args_type = TYPE_ARG_TYPES (decl_type);
1257 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1258 friend_args_type = TREE_CHAIN (friend_args_type);
1259 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1260 decl_args_type = TREE_CHAIN (decl_args_type);
1262 return compparms (decl_args_type, friend_args_type);
1266 /* DECL is a TYPE_DECL */
1268 tree decl_type = TREE_TYPE (decl);
1270 /* Make sure that both DECL and FRIEND_DECL are templates or
1273 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1274 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1276 if (need_template ^ is_template)
1278 else if (is_template)
1281 /* If both are templates, check the name of the two
1282 TEMPLATE_DECL's first because is_friend didn't. */
1283 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1284 != DECL_NAME (friend_decl))
1287 /* Now check template parameter list. */
1289 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1291 return comp_template_parms
1292 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1296 return (DECL_NAME (decl)
1297 == DECL_NAME (friend_decl));
1303 /* Register the specialization SPEC as a specialization of TMPL with
1304 the indicated ARGS. IS_FRIEND indicates whether the specialization
1305 is actually just a friend declaration. Returns SPEC, or an
1306 equivalent prior declaration, if available. */
1309 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1316 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1318 if (TREE_CODE (spec) == FUNCTION_DECL
1319 && uses_template_parms (DECL_TI_ARGS (spec)))
1320 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1321 register it; we want the corresponding TEMPLATE_DECL instead.
1322 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1323 the more obvious `uses_template_parms (spec)' to avoid problems
1324 with default function arguments. In particular, given
1325 something like this:
1327 template <class T> void f(T t1, T t = T())
1329 the default argument expression is not substituted for in an
1330 instantiation unless and until it is actually needed. */
1333 if (optimize_specialization_lookup_p (tmpl))
1334 /* We don't put these specializations in the hash table, but we might
1335 want to give an error about a mismatch. */
1336 fn = retrieve_specialization (tmpl, args, 0);
1344 hash = hash_specialization (&elt);
1347 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1349 fn = ((spec_entry *) *slot)->spec;
1354 /* We can sometimes try to re-register a specialization that we've
1355 already got. In particular, regenerate_decl_from_template calls
1356 duplicate_decls which will update the specialization list. But,
1357 we'll still get called again here anyhow. It's more convenient
1358 to simply allow this than to try to prevent it. */
1361 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1363 if (DECL_TEMPLATE_INSTANTIATION (fn))
1365 if (DECL_ODR_USED (fn)
1366 || DECL_EXPLICIT_INSTANTIATION (fn))
1368 error ("specialization of %qD after instantiation",
1370 return error_mark_node;
1375 /* This situation should occur only if the first
1376 specialization is an implicit instantiation, the
1377 second is an explicit specialization, and the
1378 implicit instantiation has not yet been used. That
1379 situation can occur if we have implicitly
1380 instantiated a member function and then specialized
1383 We can also wind up here if a friend declaration that
1384 looked like an instantiation turns out to be a
1387 template <class T> void foo(T);
1388 class S { friend void foo<>(int) };
1389 template <> void foo(int);
1391 We transform the existing DECL in place so that any
1392 pointers to it become pointers to the updated
1395 If there was a definition for the template, but not
1396 for the specialization, we want this to look as if
1397 there were no definition, and vice versa. */
1398 DECL_INITIAL (fn) = NULL_TREE;
1399 duplicate_decls (spec, fn, is_friend);
1400 /* The call to duplicate_decls will have applied
1403 An explicit specialization of a function template
1404 is inline only if it is explicitly declared to be,
1405 and independently of whether its function template
1408 to the primary function; now copy the inline bits to
1409 the various clones. */
1410 FOR_EACH_CLONE (clone, fn)
1412 DECL_DECLARED_INLINE_P (clone)
1413 = DECL_DECLARED_INLINE_P (fn);
1414 DECL_SOURCE_LOCATION (clone)
1415 = DECL_SOURCE_LOCATION (fn);
1417 check_specialization_namespace (fn);
1422 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1424 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1425 /* Dup decl failed, but this is a new definition. Set the
1426 line number so any errors match this new
1428 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1434 return duplicate_decls (spec, fn, is_friend);
1436 /* A specialization must be declared in the same namespace as the
1437 template it is specializing. */
1438 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1439 && !check_specialization_namespace (tmpl))
1440 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1442 if (slot != NULL /* !optimize_specialization_lookup_p (tmpl) */)
1444 spec_entry *entry = ggc_alloc_spec_entry ();
1445 gcc_assert (tmpl && args && spec);
1448 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1449 && PRIMARY_TEMPLATE_P (tmpl)
1450 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1451 /* TMPL is a forward declaration of a template function; keep a list
1452 of all specializations in case we need to reassign them to a friend
1453 template later in tsubst_friend_function. */
1454 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1455 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1461 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1462 TMPL and ARGS members, ignores SPEC. */
1465 eq_specializations (const void *p1, const void *p2)
1467 const spec_entry *e1 = (const spec_entry *)p1;
1468 const spec_entry *e2 = (const spec_entry *)p2;
1470 return (e1->tmpl == e2->tmpl
1471 && comp_template_args (e1->args, e2->args));
1474 /* Returns a hash for a template TMPL and template arguments ARGS. */
1477 hash_tmpl_and_args (tree tmpl, tree args)
1479 hashval_t val = DECL_UID (tmpl);
1480 return iterative_hash_template_arg (args, val);
1483 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1487 hash_specialization (const void *p)
1489 const spec_entry *e = (const spec_entry *)p;
1490 return hash_tmpl_and_args (e->tmpl, e->args);
1493 /* Recursively calculate a hash value for a template argument ARG, for use
1494 in the hash tables of template specializations. */
1497 iterative_hash_template_arg (tree arg, hashval_t val)
1499 unsigned HOST_WIDE_INT i;
1500 enum tree_code code;
1503 if (arg == NULL_TREE)
1504 return iterative_hash_object (arg, val);
1509 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1510 /* We can get one of these when re-hashing a previous entry in the middle
1511 of substituting into a pack expansion. Just look through it. */
1512 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1514 code = TREE_CODE (arg);
1515 tclass = TREE_CODE_CLASS (code);
1517 val = iterative_hash_object (code, val);
1524 case IDENTIFIER_NODE:
1525 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1529 int i, len = TREE_VEC_LENGTH (arg);
1530 for (i = 0; i < len; ++i)
1531 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1535 case TYPE_PACK_EXPANSION:
1536 case EXPR_PACK_EXPANSION:
1537 val = iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1538 return iterative_hash_template_arg (PACK_EXPANSION_EXTRA_ARGS (arg), val);
1540 case TYPE_ARGUMENT_PACK:
1541 case NONTYPE_ARGUMENT_PACK:
1542 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1545 for (; arg; arg = TREE_CHAIN (arg))
1546 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1550 for (; arg; arg = OVL_NEXT (arg))
1551 val = iterative_hash_template_arg (OVL_CURRENT (arg), val);
1557 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1559 val = iterative_hash_template_arg (field, val);
1560 val = iterative_hash_template_arg (value, val);
1566 if (!DECL_ARTIFICIAL (arg))
1568 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1569 val = iterative_hash_object (DECL_PARM_LEVEL (arg), val);
1571 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1574 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1577 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1578 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1580 case TEMPLATE_PARM_INDEX:
1581 val = iterative_hash_template_arg
1582 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1583 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1584 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1587 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1588 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1589 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1592 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1594 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1598 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1599 code = TREE_CODE (TREE_OPERAND (arg, 1));
1600 val = iterative_hash_object (code, val);
1601 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1604 /* A lambda can't appear in a template arg, but don't crash on
1606 gcc_assert (seen_error ());
1610 case IMPLICIT_CONV_EXPR:
1611 case STATIC_CAST_EXPR:
1612 case REINTERPRET_CAST_EXPR:
1613 case CONST_CAST_EXPR:
1614 case DYNAMIC_CAST_EXPR:
1616 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1617 /* Now hash operands as usual. */
1627 if (TYPE_CANONICAL (arg))
1628 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1630 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1631 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1632 /* Otherwise just compare the types during lookup. */
1635 case tcc_declaration:
1637 return iterative_hash_expr (arg, val);
1640 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1642 unsigned n = cp_tree_operand_length (arg);
1643 for (i = 0; i < n; ++i)
1644 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1652 /* Unregister the specialization SPEC as a specialization of TMPL.
1653 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1654 if the SPEC was listed as a specialization of TMPL.
1656 Note that SPEC has been ggc_freed, so we can't look inside it. */
1659 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1664 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1665 elt.args = TI_ARGS (tinfo);
1666 elt.spec = NULL_TREE;
1668 entry = (spec_entry *) htab_find (decl_specializations, &elt);
1671 gcc_assert (entry->spec == spec || entry->spec == new_spec);
1672 gcc_assert (new_spec != NULL_TREE);
1673 entry->spec = new_spec;
1680 /* Compare an entry in the local specializations hash table P1 (which
1681 is really a pointer to a TREE_LIST) with P2 (which is really a
1685 eq_local_specializations (const void *p1, const void *p2)
1687 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1690 /* Hash P1, an entry in the local specializations table. */
1693 hash_local_specialization (const void* p1)
1695 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1698 /* Like register_specialization, but for local declarations. We are
1699 registering SPEC, an instantiation of TMPL. */
1702 register_local_specialization (tree spec, tree tmpl)
1706 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1707 htab_hash_pointer (tmpl), INSERT);
1708 *slot = build_tree_list (spec, tmpl);
1711 /* TYPE is a class type. Returns true if TYPE is an explicitly
1712 specialized class. */
1715 explicit_class_specialization_p (tree type)
1717 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1719 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1722 /* Print the list of functions at FNS, going through all the overloads
1723 for each element of the list. Alternatively, FNS can not be a
1724 TREE_LIST, in which case it will be printed together with all the
1727 MORE and *STR should respectively be FALSE and NULL when the function
1728 is called from the outside. They are used internally on recursive
1729 calls. print_candidates manages the two parameters and leaves NULL
1730 in *STR when it ends. */
1733 print_candidates_1 (tree fns, bool more, const char **str)
1736 char *spaces = NULL;
1738 for (fn = fns; fn; fn = OVL_NEXT (fn))
1739 if (TREE_CODE (fn) == TREE_LIST)
1741 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1742 print_candidates_1 (TREE_VALUE (fn2),
1743 TREE_CHAIN (fn2) || more, str);
1749 /* Pick the prefix string. */
1750 if (!more && !OVL_NEXT (fns))
1752 error ("candidate is: %+#D", OVL_CURRENT (fn));
1756 *str = _("candidates are:");
1757 spaces = get_spaces (*str);
1759 error ("%s %+#D", *str, OVL_CURRENT (fn));
1760 *str = spaces ? spaces : *str;
1770 /* Print the list of candidate FNS in an error message. FNS can also
1771 be a TREE_LIST of non-functions in the case of an ambiguous lookup. */
1774 print_candidates (tree fns)
1776 const char *str = NULL;
1777 print_candidates_1 (fns, false, &str);
1778 gcc_assert (str == NULL);
1781 /* Returns the template (one of the functions given by TEMPLATE_ID)
1782 which can be specialized to match the indicated DECL with the
1783 explicit template args given in TEMPLATE_ID. The DECL may be
1784 NULL_TREE if none is available. In that case, the functions in
1785 TEMPLATE_ID are non-members.
1787 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1788 specialization of a member template.
1790 The TEMPLATE_COUNT is the number of references to qualifying
1791 template classes that appeared in the name of the function. See
1792 check_explicit_specialization for a more accurate description.
1794 TSK indicates what kind of template declaration (if any) is being
1795 declared. TSK_TEMPLATE indicates that the declaration given by
1796 DECL, though a FUNCTION_DECL, has template parameters, and is
1797 therefore a template function.
1799 The template args (those explicitly specified and those deduced)
1800 are output in a newly created vector *TARGS_OUT.
1802 If it is impossible to determine the result, an error message is
1803 issued. The error_mark_node is returned to indicate failure. */
1806 determine_specialization (tree template_id,
1809 int need_member_template,
1815 tree explicit_targs;
1816 tree candidates = NULL_TREE;
1817 /* A TREE_LIST of templates of which DECL may be a specialization.
1818 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1819 corresponding TREE_PURPOSE is the set of template arguments that,
1820 when used to instantiate the template, would produce a function
1821 with the signature of DECL. */
1822 tree templates = NULL_TREE;
1824 cp_binding_level *b;
1826 *targs_out = NULL_TREE;
1828 if (template_id == error_mark_node || decl == error_mark_node)
1829 return error_mark_node;
1831 fns = TREE_OPERAND (template_id, 0);
1832 explicit_targs = TREE_OPERAND (template_id, 1);
1834 if (fns == error_mark_node)
1835 return error_mark_node;
1837 /* Check for baselinks. */
1838 if (BASELINK_P (fns))
1839 fns = BASELINK_FUNCTIONS (fns);
1841 if (!is_overloaded_fn (fns))
1843 error ("%qD is not a function template", fns);
1844 return error_mark_node;
1847 /* Count the number of template headers specified for this
1850 for (b = current_binding_level;
1851 b->kind == sk_template_parms;
1855 for (; fns; fns = OVL_NEXT (fns))
1857 tree fn = OVL_CURRENT (fns);
1859 if (TREE_CODE (fn) == TEMPLATE_DECL)
1861 tree decl_arg_types;
1864 /* In case of explicit specialization, we need to check if
1865 the number of template headers appearing in the specialization
1866 is correct. This is usually done in check_explicit_specialization,
1867 but the check done there cannot be exhaustive when specializing
1868 member functions. Consider the following code:
1870 template <> void A<int>::f(int);
1871 template <> template <> void A<int>::f(int);
1873 Assuming that A<int> is not itself an explicit specialization
1874 already, the first line specializes "f" which is a non-template
1875 member function, whilst the second line specializes "f" which
1876 is a template member function. So both lines are syntactically
1877 correct, and check_explicit_specialization does not reject
1880 Here, we can do better, as we are matching the specialization
1881 against the declarations. We count the number of template
1882 headers, and we check if they match TEMPLATE_COUNT + 1
1883 (TEMPLATE_COUNT is the number of qualifying template classes,
1884 plus there must be another header for the member template
1887 Notice that if header_count is zero, this is not a
1888 specialization but rather a template instantiation, so there
1889 is no check we can perform here. */
1890 if (header_count && header_count != template_count + 1)
1893 /* Check that the number of template arguments at the
1894 innermost level for DECL is the same as for FN. */
1895 if (current_binding_level->kind == sk_template_parms
1896 && !current_binding_level->explicit_spec_p
1897 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1898 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1899 (current_template_parms))))
1902 /* DECL might be a specialization of FN. */
1903 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1904 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1906 /* For a non-static member function, we need to make sure
1907 that the const qualification is the same. Since
1908 get_bindings does not try to merge the "this" parameter,
1909 we must do the comparison explicitly. */
1910 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1911 && !same_type_p (TREE_VALUE (fn_arg_types),
1912 TREE_VALUE (decl_arg_types)))
1915 /* Skip the "this" parameter and, for constructors of
1916 classes with virtual bases, the VTT parameter. A
1917 full specialization of a constructor will have a VTT
1918 parameter, but a template never will. */
1920 = skip_artificial_parms_for (decl, decl_arg_types);
1922 = skip_artificial_parms_for (fn, fn_arg_types);
1924 /* Check that the number of function parameters matches.
1926 template <class T> void f(int i = 0);
1927 template <> void f<int>();
1928 The specialization f<int> is invalid but is not caught
1929 by get_bindings below. */
1930 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1933 /* Function templates cannot be specializations; there are
1934 no partial specializations of functions. Therefore, if
1935 the type of DECL does not match FN, there is no
1937 if (tsk == tsk_template)
1939 if (compparms (fn_arg_types, decl_arg_types))
1940 candidates = tree_cons (NULL_TREE, fn, candidates);
1944 /* See whether this function might be a specialization of this
1946 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1949 /* We cannot deduce template arguments that when used to
1950 specialize TMPL will produce DECL. */
1953 /* Save this template, and the arguments deduced. */
1954 templates = tree_cons (targs, fn, templates);
1956 else if (need_member_template)
1957 /* FN is an ordinary member function, and we need a
1958 specialization of a member template. */
1960 else if (TREE_CODE (fn) != FUNCTION_DECL)
1961 /* We can get IDENTIFIER_NODEs here in certain erroneous
1964 else if (!DECL_FUNCTION_MEMBER_P (fn))
1965 /* This is just an ordinary non-member function. Nothing can
1966 be a specialization of that. */
1968 else if (DECL_ARTIFICIAL (fn))
1969 /* Cannot specialize functions that are created implicitly. */
1973 tree decl_arg_types;
1975 /* This is an ordinary member function. However, since
1976 we're here, we can assume it's enclosing class is a
1977 template class. For example,
1979 template <typename T> struct S { void f(); };
1980 template <> void S<int>::f() {}
1982 Here, S<int>::f is a non-template, but S<int> is a
1983 template class. If FN has the same type as DECL, we
1984 might be in business. */
1986 if (!DECL_TEMPLATE_INFO (fn))
1987 /* Its enclosing class is an explicit specialization
1988 of a template class. This is not a candidate. */
1991 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1992 TREE_TYPE (TREE_TYPE (fn))))
1993 /* The return types differ. */
1996 /* Adjust the type of DECL in case FN is a static member. */
1997 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1998 if (DECL_STATIC_FUNCTION_P (fn)
1999 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2000 decl_arg_types = TREE_CHAIN (decl_arg_types);
2002 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
2005 candidates = tree_cons (NULL_TREE, fn, candidates);
2009 if (templates && TREE_CHAIN (templates))
2015 It is possible for a specialization with a given function
2016 signature to be instantiated from more than one function
2017 template. In such cases, explicit specification of the
2018 template arguments must be used to uniquely identify the
2019 function template specialization being specialized.
2021 Note that here, there's no suggestion that we're supposed to
2022 determine which of the candidate templates is most
2023 specialized. However, we, also have:
2027 Partial ordering of overloaded function template
2028 declarations is used in the following contexts to select
2029 the function template to which a function template
2030 specialization refers:
2032 -- when an explicit specialization refers to a function
2035 So, we do use the partial ordering rules, at least for now.
2036 This extension can only serve to make invalid programs valid,
2037 so it's safe. And, there is strong anecdotal evidence that
2038 the committee intended the partial ordering rules to apply;
2039 the EDG front end has that behavior, and John Spicer claims
2040 that the committee simply forgot to delete the wording in
2041 [temp.expl.spec]. */
2042 tree tmpl = most_specialized_instantiation (templates);
2043 if (tmpl != error_mark_node)
2046 TREE_CHAIN (templates) = NULL_TREE;
2050 if (templates == NULL_TREE && candidates == NULL_TREE)
2052 error ("template-id %qD for %q+D does not match any template "
2053 "declaration", template_id, decl);
2054 if (header_count && header_count != template_count + 1)
2055 inform (input_location, "saw %d %<template<>%>, need %d for "
2056 "specializing a member function template",
2057 header_count, template_count + 1);
2058 return error_mark_node;
2060 else if ((templates && TREE_CHAIN (templates))
2061 || (candidates && TREE_CHAIN (candidates))
2062 || (templates && candidates))
2064 error ("ambiguous template specialization %qD for %q+D",
2066 candidates = chainon (candidates, templates);
2067 print_candidates (candidates);
2068 return error_mark_node;
2071 /* We have one, and exactly one, match. */
2074 tree fn = TREE_VALUE (candidates);
2075 *targs_out = copy_node (DECL_TI_ARGS (fn));
2076 /* DECL is a re-declaration or partial instantiation of a template
2078 if (TREE_CODE (fn) == TEMPLATE_DECL)
2080 /* It was a specialization of an ordinary member function in a
2082 return DECL_TI_TEMPLATE (fn);
2085 /* It was a specialization of a template. */
2086 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2087 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2089 *targs_out = copy_node (targs);
2090 SET_TMPL_ARGS_LEVEL (*targs_out,
2091 TMPL_ARGS_DEPTH (*targs_out),
2092 TREE_PURPOSE (templates));
2095 *targs_out = TREE_PURPOSE (templates);
2096 return TREE_VALUE (templates);
2099 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2100 but with the default argument values filled in from those in the
2104 copy_default_args_to_explicit_spec_1 (tree spec_types,
2107 tree new_spec_types;
2112 if (spec_types == void_list_node)
2113 return void_list_node;
2115 /* Substitute into the rest of the list. */
2117 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2118 TREE_CHAIN (tmpl_types));
2120 /* Add the default argument for this parameter. */
2121 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2122 TREE_VALUE (spec_types),
2126 /* DECL is an explicit specialization. Replicate default arguments
2127 from the template it specializes. (That way, code like:
2129 template <class T> void f(T = 3);
2130 template <> void f(double);
2133 works, as required.) An alternative approach would be to look up
2134 the correct default arguments at the call-site, but this approach
2135 is consistent with how implicit instantiations are handled. */
2138 copy_default_args_to_explicit_spec (tree decl)
2143 tree new_spec_types;
2147 tree object_type = NULL_TREE;
2148 tree in_charge = NULL_TREE;
2149 tree vtt = NULL_TREE;
2151 /* See if there's anything we need to do. */
2152 tmpl = DECL_TI_TEMPLATE (decl);
2153 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2154 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2155 if (TREE_PURPOSE (t))
2160 old_type = TREE_TYPE (decl);
2161 spec_types = TYPE_ARG_TYPES (old_type);
2163 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2165 /* Remove the this pointer, but remember the object's type for
2167 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2168 spec_types = TREE_CHAIN (spec_types);
2169 tmpl_types = TREE_CHAIN (tmpl_types);
2171 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2173 /* DECL may contain more parameters than TMPL due to the extra
2174 in-charge parameter in constructors and destructors. */
2175 in_charge = spec_types;
2176 spec_types = TREE_CHAIN (spec_types);
2178 if (DECL_HAS_VTT_PARM_P (decl))
2181 spec_types = TREE_CHAIN (spec_types);
2185 /* Compute the merged default arguments. */
2187 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2189 /* Compute the new FUNCTION_TYPE. */
2193 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2198 /* Put the in-charge parameter back. */
2199 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2200 TREE_VALUE (in_charge),
2203 new_type = build_method_type_directly (object_type,
2204 TREE_TYPE (old_type),
2208 new_type = build_function_type (TREE_TYPE (old_type),
2210 new_type = cp_build_type_attribute_variant (new_type,
2211 TYPE_ATTRIBUTES (old_type));
2212 new_type = build_exception_variant (new_type,
2213 TYPE_RAISES_EXCEPTIONS (old_type));
2214 TREE_TYPE (decl) = new_type;
2217 /* Check to see if the function just declared, as indicated in
2218 DECLARATOR, and in DECL, is a specialization of a function
2219 template. We may also discover that the declaration is an explicit
2220 instantiation at this point.
2222 Returns DECL, or an equivalent declaration that should be used
2223 instead if all goes well. Issues an error message if something is
2224 amiss. Returns error_mark_node if the error is not easily
2227 FLAGS is a bitmask consisting of the following flags:
2229 2: The function has a definition.
2230 4: The function is a friend.
2232 The TEMPLATE_COUNT is the number of references to qualifying
2233 template classes that appeared in the name of the function. For
2236 template <class T> struct S { void f(); };
2239 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2240 classes are not counted in the TEMPLATE_COUNT, so that in
2242 template <class T> struct S {};
2243 template <> struct S<int> { void f(); }
2244 template <> void S<int>::f();
2246 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2247 invalid; there should be no template <>.)
2249 If the function is a specialization, it is marked as such via
2250 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2251 is set up correctly, and it is added to the list of specializations
2252 for that template. */
2255 check_explicit_specialization (tree declarator,
2260 int have_def = flags & 2;
2261 int is_friend = flags & 4;
2262 int specialization = 0;
2263 int explicit_instantiation = 0;
2264 int member_specialization = 0;
2265 tree ctype = DECL_CLASS_CONTEXT (decl);
2266 tree dname = DECL_NAME (decl);
2271 if (!processing_specialization)
2274 tsk = tsk_excessive_parms;
2277 tsk = current_tmpl_spec_kind (template_count);
2282 if (processing_specialization)
2285 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2287 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2290 /* This could be something like:
2292 template <class T> void f(T);
2293 class S { friend void f<>(int); } */
2297 /* This case handles bogus declarations like template <>
2298 template <class T> void f<int>(); */
2300 error ("template-id %qD in declaration of primary template",
2307 case tsk_invalid_member_spec:
2308 /* The error has already been reported in
2309 check_specialization_scope. */
2310 return error_mark_node;
2312 case tsk_invalid_expl_inst:
2313 error ("template parameter list used in explicit instantiation");
2319 error ("definition provided for explicit instantiation");
2321 explicit_instantiation = 1;
2324 case tsk_excessive_parms:
2325 case tsk_insufficient_parms:
2326 if (tsk == tsk_excessive_parms)
2327 error ("too many template parameter lists in declaration of %qD",
2329 else if (template_header_count)
2330 error("too few template parameter lists in declaration of %qD", decl);
2332 error("explicit specialization of %qD must be introduced by "
2333 "%<template <>%>", decl);
2337 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2339 member_specialization = 1;
2345 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2347 /* This case handles bogus declarations like template <>
2348 template <class T> void f<int>(); */
2350 if (uses_template_parms (declarator))
2351 error ("function template partial specialization %qD "
2352 "is not allowed", declarator);
2354 error ("template-id %qD in declaration of primary template",
2359 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2360 /* This is a specialization of a member template, without
2361 specialization the containing class. Something like:
2363 template <class T> struct S {
2364 template <class U> void f (U);
2366 template <> template <class U> void S<int>::f(U) {}
2368 That's a specialization -- but of the entire template. */
2376 if (specialization || member_specialization)
2378 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2379 for (; t; t = TREE_CHAIN (t))
2380 if (TREE_PURPOSE (t))
2382 permerror (input_location,
2383 "default argument specified in explicit specialization");
2388 if (specialization || member_specialization || explicit_instantiation)
2390 tree tmpl = NULL_TREE;
2391 tree targs = NULL_TREE;
2393 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2394 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2398 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2403 /* If there is no class context, the explicit instantiation
2404 must be at namespace scope. */
2405 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2407 /* Find the namespace binding, using the declaration
2409 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2411 if (fns == error_mark_node || !is_overloaded_fn (fns))
2413 error ("%qD is not a template function", dname);
2414 fns = error_mark_node;
2418 tree fn = OVL_CURRENT (fns);
2419 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2420 CP_DECL_CONTEXT (fn)))
2421 error ("%qD is not declared in %qD",
2422 decl, current_namespace);
2426 declarator = lookup_template_function (fns, NULL_TREE);
2429 if (declarator == error_mark_node)
2430 return error_mark_node;
2432 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2434 if (!explicit_instantiation)
2435 /* A specialization in class scope. This is invalid,
2436 but the error will already have been flagged by
2437 check_specialization_scope. */
2438 return error_mark_node;
2441 /* It's not valid to write an explicit instantiation in
2444 class C { template void f(); }
2446 This case is caught by the parser. However, on
2449 template class C { void f(); };
2451 (which is invalid) we can get here. The error will be
2458 else if (ctype != NULL_TREE
2459 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2462 /* Find the list of functions in ctype that have the same
2463 name as the declared function. */
2464 tree name = TREE_OPERAND (declarator, 0);
2465 tree fns = NULL_TREE;
2468 if (constructor_name_p (name, ctype))
2470 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2472 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2473 : !CLASSTYPE_DESTRUCTORS (ctype))
2475 /* From [temp.expl.spec]:
2477 If such an explicit specialization for the member
2478 of a class template names an implicitly-declared
2479 special member function (clause _special_), the
2480 program is ill-formed.
2482 Similar language is found in [temp.explicit]. */
2483 error ("specialization of implicitly-declared special member function");
2484 return error_mark_node;
2487 name = is_constructor ? ctor_identifier : dtor_identifier;
2490 if (!DECL_CONV_FN_P (decl))
2492 idx = lookup_fnfields_1 (ctype, name);
2494 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2498 VEC(tree,gc) *methods;
2501 /* For a type-conversion operator, we cannot do a
2502 name-based lookup. We might be looking for `operator
2503 int' which will be a specialization of `operator T'.
2504 So, we find *all* the conversion operators, and then
2505 select from them. */
2508 methods = CLASSTYPE_METHOD_VEC (ctype);
2510 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2511 VEC_iterate (tree, methods, idx, ovl);
2514 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2515 /* There are no more conversion functions. */
2518 /* Glue all these conversion functions together
2519 with those we already have. */
2520 for (; ovl; ovl = OVL_NEXT (ovl))
2521 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2525 if (fns == NULL_TREE)
2527 error ("no member function %qD declared in %qT", name, ctype);
2528 return error_mark_node;
2531 TREE_OPERAND (declarator, 0) = fns;
2534 /* Figure out what exactly is being specialized at this point.
2535 Note that for an explicit instantiation, even one for a
2536 member function, we cannot tell apriori whether the
2537 instantiation is for a member template, or just a member
2538 function of a template class. Even if a member template is
2539 being instantiated, the member template arguments may be
2540 elided if they can be deduced from the rest of the
2542 tmpl = determine_specialization (declarator, decl,
2544 member_specialization,
2548 if (!tmpl || tmpl == error_mark_node)
2549 /* We couldn't figure out what this declaration was
2551 return error_mark_node;
2554 tree gen_tmpl = most_general_template (tmpl);
2556 if (explicit_instantiation)
2558 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2559 is done by do_decl_instantiation later. */
2561 int arg_depth = TMPL_ARGS_DEPTH (targs);
2562 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2564 if (arg_depth > parm_depth)
2566 /* If TMPL is not the most general template (for
2567 example, if TMPL is a friend template that is
2568 injected into namespace scope), then there will
2569 be too many levels of TARGS. Remove some of them
2574 new_targs = make_tree_vec (parm_depth);
2575 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2576 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2577 = TREE_VEC_ELT (targs, i);
2581 return instantiate_template (tmpl, targs, tf_error);
2584 /* If we thought that the DECL was a member function, but it
2585 turns out to be specializing a static member function,
2586 make DECL a static member function as well. */
2587 if (DECL_STATIC_FUNCTION_P (tmpl)
2588 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2589 revert_static_member_fn (decl);
2591 /* If this is a specialization of a member template of a
2592 template class, we want to return the TEMPLATE_DECL, not
2593 the specialization of it. */
2594 if (tsk == tsk_template)
2596 tree result = DECL_TEMPLATE_RESULT (tmpl);
2597 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2598 DECL_INITIAL (result) = NULL_TREE;
2602 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2603 DECL_SOURCE_LOCATION (result)
2604 = DECL_SOURCE_LOCATION (decl);
2605 /* We want to use the argument list specified in the
2606 definition, not in the original declaration. */
2607 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2608 for (parm = DECL_ARGUMENTS (result); parm;
2609 parm = DECL_CHAIN (parm))
2610 DECL_CONTEXT (parm) = result;
2612 return register_specialization (tmpl, gen_tmpl, targs,
2616 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2617 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2619 /* Inherit default function arguments from the template
2620 DECL is specializing. */
2621 copy_default_args_to_explicit_spec (decl);
2623 /* This specialization has the same protection as the
2624 template it specializes. */
2625 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2626 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2628 /* 7.1.1-1 [dcl.stc]
2630 A storage-class-specifier shall not be specified in an
2631 explicit specialization...
2633 The parser rejects these, so unless action is taken here,
2634 explicit function specializations will always appear with
2637 The action recommended by the C++ CWG in response to C++
2638 defect report 605 is to make the storage class and linkage
2639 of the explicit specialization match the templated function:
2641 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2643 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2645 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2646 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2648 /* This specialization has the same linkage and visibility as
2649 the function template it specializes. */
2650 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2651 if (! TREE_PUBLIC (decl))
2653 DECL_INTERFACE_KNOWN (decl) = 1;
2654 DECL_NOT_REALLY_EXTERN (decl) = 1;
2656 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2657 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2659 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2660 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2664 /* If DECL is a friend declaration, declared using an
2665 unqualified name, the namespace associated with DECL may
2666 have been set incorrectly. For example, in:
2668 template <typename T> void f(T);
2670 struct S { friend void f<int>(int); }
2673 we will have set the DECL_CONTEXT for the friend
2674 declaration to N, rather than to the global namespace. */
2675 if (DECL_NAMESPACE_SCOPE_P (decl))
2676 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2678 if (is_friend && !have_def)
2679 /* This is not really a declaration of a specialization.
2680 It's just the name of an instantiation. But, it's not
2681 a request for an instantiation, either. */
2682 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2683 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2684 /* This is indeed a specialization. In case of constructors
2685 and destructors, we need in-charge and not-in-charge
2686 versions in V3 ABI. */
2687 clone_function_decl (decl, /*update_method_vec_p=*/0);
2689 /* Register this specialization so that we can find it
2691 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2698 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2699 parameters. These are represented in the same format used for
2700 DECL_TEMPLATE_PARMS. */
2703 comp_template_parms (const_tree parms1, const_tree parms2)
2708 if (parms1 == parms2)
2711 for (p1 = parms1, p2 = parms2;
2712 p1 != NULL_TREE && p2 != NULL_TREE;
2713 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2715 tree t1 = TREE_VALUE (p1);
2716 tree t2 = TREE_VALUE (p2);
2719 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2720 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2722 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2725 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2727 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2728 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2730 /* If either of the template parameters are invalid, assume
2731 they match for the sake of error recovery. */
2732 if (parm1 == error_mark_node || parm2 == error_mark_node)
2735 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2738 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2739 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2740 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2742 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2747 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2748 /* One set of parameters has more parameters lists than the
2755 /* Determine whether PARM is a parameter pack. */
2758 template_parameter_pack_p (const_tree parm)
2760 /* Determine if we have a non-type template parameter pack. */
2761 if (TREE_CODE (parm) == PARM_DECL)
2762 return (DECL_TEMPLATE_PARM_P (parm)
2763 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2764 if (TREE_CODE (parm) == TEMPLATE_PARM_INDEX)
2765 return TEMPLATE_PARM_PARAMETER_PACK (parm);
2767 /* If this is a list of template parameters, we could get a
2768 TYPE_DECL or a TEMPLATE_DECL. */
2769 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2770 parm = TREE_TYPE (parm);
2772 /* Otherwise it must be a type template parameter. */
2773 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2774 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2775 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2778 /* Determine if T is a function parameter pack. */
2781 function_parameter_pack_p (const_tree t)
2783 if (t && TREE_CODE (t) == PARM_DECL)
2784 return FUNCTION_PARAMETER_PACK_P (t);
2788 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2789 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2792 get_function_template_decl (const_tree primary_func_tmpl_inst)
2794 if (! primary_func_tmpl_inst
2795 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2796 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2799 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2802 /* Return true iff the function parameter PARAM_DECL was expanded
2803 from the function parameter pack PACK. */
2806 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2808 if (DECL_ARTIFICIAL (param_decl)
2809 || !function_parameter_pack_p (pack))
2812 /* The parameter pack and its pack arguments have the same
2814 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2817 /* Determine whether ARGS describes a variadic template args list,
2818 i.e., one that is terminated by a template argument pack. */
2821 template_args_variadic_p (tree args)
2826 if (args == NULL_TREE)
2829 args = INNERMOST_TEMPLATE_ARGS (args);
2830 nargs = TREE_VEC_LENGTH (args);
2835 last_parm = TREE_VEC_ELT (args, nargs - 1);
2837 return ARGUMENT_PACK_P (last_parm);
2840 /* Generate a new name for the parameter pack name NAME (an
2841 IDENTIFIER_NODE) that incorporates its */
2844 make_ith_pack_parameter_name (tree name, int i)
2846 /* Munge the name to include the parameter index. */
2847 #define NUMBUF_LEN 128
2848 char numbuf[NUMBUF_LEN];
2852 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2853 newname_len = IDENTIFIER_LENGTH (name)
2854 + strlen (numbuf) + 2;
2855 newname = (char*)alloca (newname_len);
2856 snprintf (newname, newname_len,
2857 "%s#%i", IDENTIFIER_POINTER (name), i);
2858 return get_identifier (newname);
2861 /* Return true if T is a primary function, class or alias template
2865 primary_template_instantiation_p (const_tree t)
2870 if (TREE_CODE (t) == FUNCTION_DECL)
2871 return DECL_LANG_SPECIFIC (t)
2872 && DECL_TEMPLATE_INSTANTIATION (t)
2873 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2874 else if (CLASS_TYPE_P (t) && !TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2875 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2876 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2878 && TYPE_TEMPLATE_INFO (t)
2879 && PRIMARY_TEMPLATE_P (TYPE_TI_TEMPLATE (t))
2880 && DECL_TEMPLATE_INSTANTIATION (TYPE_NAME (t)))
2885 /* Return true if PARM is a template template parameter. */
2888 template_template_parameter_p (const_tree parm)
2890 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2893 /* Return the template parameters of T if T is a
2894 primary template instantiation, NULL otherwise. */
2897 get_primary_template_innermost_parameters (const_tree t)
2899 tree parms = NULL, template_info = NULL;
2901 if ((template_info = get_template_info (t))
2902 && primary_template_instantiation_p (t))
2903 parms = INNERMOST_TEMPLATE_PARMS
2904 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2909 /* Return the template parameters of the LEVELth level from the full list
2910 of template parameters PARMS. */
2913 get_template_parms_at_level (tree parms, int level)
2917 || TREE_CODE (parms) != TREE_LIST
2918 || level > TMPL_PARMS_DEPTH (parms))
2921 for (p = parms; p; p = TREE_CHAIN (p))
2922 if (TMPL_PARMS_DEPTH (p) == level)
2928 /* Returns the template arguments of T if T is a template instantiation,
2932 get_template_innermost_arguments (const_tree t)
2934 tree args = NULL, template_info = NULL;
2936 if ((template_info = get_template_info (t))
2937 && TI_ARGS (template_info))
2938 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2943 /* Return the argument pack elements of T if T is a template argument pack,
2947 get_template_argument_pack_elems (const_tree t)
2949 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2950 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2953 return ARGUMENT_PACK_ARGS (t);
2956 /* Structure used to track the progress of find_parameter_packs_r. */
2957 struct find_parameter_pack_data
2959 /* TREE_LIST that will contain all of the parameter packs found by
2961 tree* parameter_packs;
2963 /* Set of AST nodes that have been visited by the traversal. */
2964 struct pointer_set_t *visited;
2967 /* Identifies all of the argument packs that occur in a template
2968 argument and appends them to the TREE_LIST inside DATA, which is a
2969 find_parameter_pack_data structure. This is a subroutine of
2970 make_pack_expansion and uses_parameter_packs. */
2972 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2975 struct find_parameter_pack_data* ppd =
2976 (struct find_parameter_pack_data*)data;
2977 bool parameter_pack_p = false;
2979 /* Handle type aliases/typedefs. */
2982 && TREE_CODE (TYPE_NAME (t)) == TYPE_DECL
2983 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2985 if (TYPE_TEMPLATE_INFO (t))
2986 cp_walk_tree (&TYPE_TI_ARGS (t),
2987 &find_parameter_packs_r,
2993 /* Identify whether this is a parameter pack or not. */
2994 switch (TREE_CODE (t))
2996 case TEMPLATE_PARM_INDEX:
2997 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2998 parameter_pack_p = true;
3001 case TEMPLATE_TYPE_PARM:
3002 t = TYPE_MAIN_VARIANT (t);
3003 case TEMPLATE_TEMPLATE_PARM:
3004 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3005 parameter_pack_p = true;
3009 if (FUNCTION_PARAMETER_PACK_P (t))
3011 /* We don't want to walk into the type of a PARM_DECL,
3012 because we don't want to see the type parameter pack. */
3014 parameter_pack_p = true;
3019 parameter_pack_p = true;
3022 /* Not a parameter pack. */
3026 if (parameter_pack_p)
3028 /* Add this parameter pack to the list. */
3029 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
3033 cp_walk_tree (&TYPE_CONTEXT (t),
3034 &find_parameter_packs_r, ppd, ppd->visited);
3036 /* This switch statement will return immediately if we don't find a
3038 switch (TREE_CODE (t))
3040 case TEMPLATE_PARM_INDEX:
3043 case BOUND_TEMPLATE_TEMPLATE_PARM:
3044 /* Check the template itself. */
3045 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
3046 &find_parameter_packs_r, ppd, ppd->visited);
3047 /* Check the template arguments. */
3048 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
3053 case TEMPLATE_TYPE_PARM:
3054 case TEMPLATE_TEMPLATE_PARM:
3061 if (TYPE_PTRMEMFUNC_P (t))
3067 if (TYPE_TEMPLATE_INFO (t))
3068 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3069 &find_parameter_packs_r, ppd, ppd->visited);
3076 cp_walk_tree (&TREE_TYPE (t),
3077 &find_parameter_packs_r, ppd, ppd->visited);
3081 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3086 case TYPE_PACK_EXPANSION:
3087 case EXPR_PACK_EXPANSION:
3092 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3097 case IDENTIFIER_NODE:
3098 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3110 /* Determines if the expression or type T uses any parameter packs. */
3112 uses_parameter_packs (tree t)
3114 tree parameter_packs = NULL_TREE;
3115 struct find_parameter_pack_data ppd;
3116 ppd.parameter_packs = ¶meter_packs;
3117 ppd.visited = pointer_set_create ();
3118 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3119 pointer_set_destroy (ppd.visited);
3120 return parameter_packs != NULL_TREE;
3123 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3124 representation a base-class initializer into a parameter pack
3125 expansion. If all goes well, the resulting node will be an
3126 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3129 make_pack_expansion (tree arg)
3132 tree parameter_packs = NULL_TREE;
3133 bool for_types = false;
3134 struct find_parameter_pack_data ppd;
3136 if (!arg || arg == error_mark_node)
3139 if (TREE_CODE (arg) == TREE_LIST)
3141 /* The only time we will see a TREE_LIST here is for a base
3142 class initializer. In this case, the TREE_PURPOSE will be a
3143 _TYPE node (representing the base class expansion we're
3144 initializing) and the TREE_VALUE will be a TREE_LIST
3145 containing the initialization arguments.
3147 The resulting expansion looks somewhat different from most
3148 expansions. Rather than returning just one _EXPANSION, we
3149 return a TREE_LIST whose TREE_PURPOSE is a
3150 TYPE_PACK_EXPANSION containing the bases that will be
3151 initialized. The TREE_VALUE will be identical to the
3152 original TREE_VALUE, which is a list of arguments that will
3153 be passed to each base. We do not introduce any new pack
3154 expansion nodes into the TREE_VALUE (although it is possible
3155 that some already exist), because the TREE_PURPOSE and
3156 TREE_VALUE all need to be expanded together with the same
3157 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3158 resulting TREE_PURPOSE will mention the parameter packs in
3159 both the bases and the arguments to the bases. */
3162 tree parameter_packs = NULL_TREE;
3164 /* Determine which parameter packs will be used by the base
3166 ppd.visited = pointer_set_create ();
3167 ppd.parameter_packs = ¶meter_packs;
3168 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3171 if (parameter_packs == NULL_TREE)
3173 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3174 pointer_set_destroy (ppd.visited);
3175 return error_mark_node;
3178 if (TREE_VALUE (arg) != void_type_node)
3180 /* Collect the sets of parameter packs used in each of the
3181 initialization arguments. */
3182 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3184 /* Determine which parameter packs will be expanded in this
3186 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3191 pointer_set_destroy (ppd.visited);
3193 /* Create the pack expansion type for the base type. */
3194 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3195 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3196 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3198 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3199 they will rarely be compared to anything. */
3200 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3202 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3205 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3208 /* Build the PACK_EXPANSION_* node. */
3210 ? cxx_make_type (TYPE_PACK_EXPANSION)
3211 : make_node (EXPR_PACK_EXPANSION);
3212 SET_PACK_EXPANSION_PATTERN (result, arg);
3213 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3215 /* Propagate type and const-expression information. */
3216 TREE_TYPE (result) = TREE_TYPE (arg);
3217 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3220 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3221 they will rarely be compared to anything. */
3222 SET_TYPE_STRUCTURAL_EQUALITY (result);
3224 /* Determine which parameter packs will be expanded. */
3225 ppd.parameter_packs = ¶meter_packs;
3226 ppd.visited = pointer_set_create ();
3227 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3228 pointer_set_destroy (ppd.visited);
3230 /* Make sure we found some parameter packs. */
3231 if (parameter_packs == NULL_TREE)
3234 error ("expansion pattern %<%T%> contains no argument packs", arg);
3236 error ("expansion pattern %<%E%> contains no argument packs", arg);
3237 return error_mark_node;
3239 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3244 /* Checks T for any "bare" parameter packs, which have not yet been
3245 expanded, and issues an error if any are found. This operation can
3246 only be done on full expressions or types (e.g., an expression
3247 statement, "if" condition, etc.), because we could have expressions like:
3249 foo(f(g(h(args)))...)
3251 where "args" is a parameter pack. check_for_bare_parameter_packs
3252 should not be called for the subexpressions args, h(args),
3253 g(h(args)), or f(g(h(args))), because we would produce erroneous
3256 Returns TRUE and emits an error if there were bare parameter packs,
3257 returns FALSE otherwise. */
3259 check_for_bare_parameter_packs (tree t)
3261 tree parameter_packs = NULL_TREE;
3262 struct find_parameter_pack_data ppd;
3264 if (!processing_template_decl || !t || t == error_mark_node)
3267 if (TREE_CODE (t) == TYPE_DECL)
3270 ppd.parameter_packs = ¶meter_packs;
3271 ppd.visited = pointer_set_create ();
3272 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3273 pointer_set_destroy (ppd.visited);
3275 if (parameter_packs)
3277 error ("parameter packs not expanded with %<...%>:");
3278 while (parameter_packs)
3280 tree pack = TREE_VALUE (parameter_packs);
3281 tree name = NULL_TREE;
3283 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3284 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3285 name = TYPE_NAME (pack);
3286 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3287 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3289 name = DECL_NAME (pack);
3292 inform (input_location, " %qD", name);
3294 inform (input_location, " <anonymous>");
3296 parameter_packs = TREE_CHAIN (parameter_packs);
3305 /* Expand any parameter packs that occur in the template arguments in
3308 expand_template_argument_pack (tree args)
3310 tree result_args = NULL_TREE;
3311 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3312 int num_result_args = -1;
3313 int non_default_args_count = -1;
3315 /* First, determine if we need to expand anything, and the number of
3316 slots we'll need. */
3317 for (in_arg = 0; in_arg < nargs; ++in_arg)
3319 tree arg = TREE_VEC_ELT (args, in_arg);
3320 if (arg == NULL_TREE)
3322 if (ARGUMENT_PACK_P (arg))
3324 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3325 if (num_result_args < 0)
3326 num_result_args = in_arg + num_packed;
3328 num_result_args += num_packed;
3332 if (num_result_args >= 0)
3337 /* If no expansion is necessary, we're done. */
3338 if (num_result_args < 0)
3341 /* Expand arguments. */
3342 result_args = make_tree_vec (num_result_args);
3343 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3344 non_default_args_count =
3345 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3346 for (in_arg = 0; in_arg < nargs; ++in_arg)
3348 tree arg = TREE_VEC_ELT (args, in_arg);
3349 if (ARGUMENT_PACK_P (arg))
3351 tree packed = ARGUMENT_PACK_ARGS (arg);
3352 int i, num_packed = TREE_VEC_LENGTH (packed);
3353 for (i = 0; i < num_packed; ++i, ++out_arg)
3354 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3355 if (non_default_args_count > 0)
3356 non_default_args_count += num_packed;
3360 TREE_VEC_ELT (result_args, out_arg) = arg;
3364 if (non_default_args_count >= 0)
3365 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3369 /* Checks if DECL shadows a template parameter.
3371 [temp.local]: A template-parameter shall not be redeclared within its
3372 scope (including nested scopes).
3374 Emits an error and returns TRUE if the DECL shadows a parameter,
3375 returns FALSE otherwise. */
3378 check_template_shadow (tree decl)
3382 /* If we're not in a template, we can't possibly shadow a template
3384 if (!current_template_parms)
3387 /* Figure out what we're shadowing. */
3388 if (TREE_CODE (decl) == OVERLOAD)
3389 decl = OVL_CURRENT (decl);
3390 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3392 /* If there's no previous binding for this name, we're not shadowing
3393 anything, let alone a template parameter. */
3397 /* If we're not shadowing a template parameter, we're done. Note
3398 that OLDDECL might be an OVERLOAD (or perhaps even an
3399 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3401 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3404 /* We check for decl != olddecl to avoid bogus errors for using a
3405 name inside a class. We check TPFI to avoid duplicate errors for
3406 inline member templates. */
3408 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3411 error ("declaration of %q+#D", decl);
3412 error (" shadows template parm %q+#D", olddecl);
3416 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3417 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3418 template parameters. */
3421 build_template_parm_index (int index,
3428 tree t = make_node (TEMPLATE_PARM_INDEX);
3429 TEMPLATE_PARM_IDX (t) = index;
3430 TEMPLATE_PARM_LEVEL (t) = level;
3431 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3432 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3433 TEMPLATE_PARM_DECL (t) = decl;
3434 TREE_TYPE (t) = type;
3435 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3436 TREE_READONLY (t) = TREE_READONLY (decl);
3441 /* Find the canonical type parameter for the given template type
3442 parameter. Returns the canonical type parameter, which may be TYPE
3443 if no such parameter existed. */
3446 canonical_type_parameter (tree type)
3449 int idx = TEMPLATE_TYPE_IDX (type);
3450 if (!canonical_template_parms)
3451 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3453 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3454 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3456 list = VEC_index (tree, canonical_template_parms, idx);
3457 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3458 list = TREE_CHAIN (list);
3461 return TREE_VALUE (list);
3464 VEC_replace(tree, canonical_template_parms, idx,
3465 tree_cons (NULL_TREE, type,
3466 VEC_index (tree, canonical_template_parms, idx)));
3471 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3472 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3473 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3474 new one is created. */
3477 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3478 tsubst_flags_t complain)
3480 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3481 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3482 != TEMPLATE_PARM_LEVEL (index) - levels)
3483 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3485 tree orig_decl = TEMPLATE_PARM_DECL (index);
3488 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3489 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3490 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3491 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3492 DECL_ARTIFICIAL (decl) = 1;
3493 SET_DECL_TEMPLATE_PARM_P (decl);
3495 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3496 TEMPLATE_PARM_LEVEL (index) - levels,
3497 TEMPLATE_PARM_ORIG_LEVEL (index),
3498 TEMPLATE_PARM_NUM_SIBLINGS (index),
3500 TEMPLATE_PARM_DESCENDANTS (index) = t;
3501 TEMPLATE_PARM_PARAMETER_PACK (t)
3502 = TEMPLATE_PARM_PARAMETER_PACK (index);
3504 /* Template template parameters need this. */
3505 if (TREE_CODE (decl) == TEMPLATE_DECL)
3506 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3507 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3511 return TEMPLATE_PARM_DESCENDANTS (index);
3514 /* Process information from new template parameter PARM and append it
3515 to the LIST being built. This new parameter is a non-type
3516 parameter iff IS_NON_TYPE is true. This new parameter is a
3517 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3518 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3519 parameter list PARM belongs to. This is used used to create a
3520 proper canonical type for the type of PARM that is to be created,
3521 iff PARM is a type. If the size is not known, this parameter shall
3525 process_template_parm (tree list, location_t parm_loc, tree parm,
3526 bool is_non_type, bool is_parameter_pack,
3527 unsigned num_template_parms)
3534 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3535 defval = TREE_PURPOSE (parm);
3539 tree p = tree_last (list);
3541 if (p && TREE_VALUE (p) != error_mark_node)
3544 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3545 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3547 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3557 parm = TREE_VALUE (parm);
3559 SET_DECL_TEMPLATE_PARM_P (parm);
3561 if (TREE_TYPE (parm) == error_mark_node)
3563 err_parm_list = build_tree_list (defval, parm);
3564 TREE_VALUE (err_parm_list) = error_mark_node;
3565 return chainon (list, err_parm_list);
3571 The top-level cv-qualifiers on the template-parameter are
3572 ignored when determining its type. */
3573 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3574 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3576 err_parm_list = build_tree_list (defval, parm);
3577 TREE_VALUE (err_parm_list) = error_mark_node;
3578 return chainon (list, err_parm_list);
3581 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3583 /* This template parameter is not a parameter pack, but it
3584 should be. Complain about "bare" parameter packs. */
3585 check_for_bare_parameter_packs (TREE_TYPE (parm));
3587 /* Recover by calling this a parameter pack. */
3588 is_parameter_pack = true;
3592 /* A template parameter is not modifiable. */
3593 TREE_CONSTANT (parm) = 1;
3594 TREE_READONLY (parm) = 1;
3595 decl = build_decl (parm_loc,
3596 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3597 TREE_CONSTANT (decl) = 1;
3598 TREE_READONLY (decl) = 1;
3599 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3600 = build_template_parm_index (idx, processing_template_decl,
3601 processing_template_decl,
3603 decl, TREE_TYPE (parm));
3605 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3606 = is_parameter_pack;
3611 parm = TREE_VALUE (TREE_VALUE (parm));
3613 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3615 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3616 /* This is for distinguishing between real templates and template
3617 template parameters */
3618 TREE_TYPE (parm) = t;
3619 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3624 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3625 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3626 decl = build_decl (parm_loc,
3627 TYPE_DECL, parm, t);
3630 TYPE_NAME (t) = decl;
3631 TYPE_STUB_DECL (t) = decl;
3633 TEMPLATE_TYPE_PARM_INDEX (t)
3634 = build_template_parm_index (idx, processing_template_decl,
3635 processing_template_decl,
3637 decl, TREE_TYPE (parm));
3638 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3639 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3641 DECL_ARTIFICIAL (decl) = 1;
3642 SET_DECL_TEMPLATE_PARM_P (decl);
3644 parm = build_tree_list (defval, parm);
3645 return chainon (list, parm);
3648 /* The end of a template parameter list has been reached. Process the
3649 tree list into a parameter vector, converting each parameter into a more
3650 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3654 end_template_parm_list (tree parms)
3658 tree saved_parmlist = make_tree_vec (list_length (parms));
3660 current_template_parms
3661 = tree_cons (size_int (processing_template_decl),
3662 saved_parmlist, current_template_parms);
3664 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3666 next = TREE_CHAIN (parm);
3667 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3668 TREE_CHAIN (parm) = NULL_TREE;
3671 --processing_template_parmlist;
3673 return saved_parmlist;
3676 /* Create a new type almost identical to TYPE but which has the
3677 following differences:
3679 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3680 template sibling parameters of T.
3682 2/ T has a new canonical type that matches the new number
3685 3/ From now on, T is going to be what lookups referring to the
3686 name of TYPE will return. No lookup should return TYPE anymore.
3688 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3690 This is a subroutine of fixup_template_parms. */
3693 fixup_template_type_parm_type (tree type, int num_parms)
3695 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3697 /* This is the decl which name is inserted into the symbol table for
3698 the template parm type. So whenever we lookup the type name, this
3699 is the DECL we get. */
3702 /* Do not fix up the type twice. */
3703 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3706 t = copy_type (type);
3707 decl = TYPE_NAME (t);
3709 TYPE_MAIN_VARIANT (t) = t;
3710 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3711 TYPE_POINTER_TO (t) = 0;
3712 TYPE_REFERENCE_TO (t) = 0;
3714 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3715 TEMPLATE_PARM_LEVEL (orig_idx),
3716 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3719 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3720 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3721 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3723 TYPE_STUB_DECL (t) = decl;
3724 TEMPLATE_TYPE_DECL (t) = decl;
3725 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3726 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3728 /* Update the type associated to the type name stored in the symbol
3729 table. Now, whenever the type name is looked up, the resulting
3730 type is properly fixed up. */
3731 TREE_TYPE (decl) = t;
3733 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3738 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3739 identical to I, but that is fixed up as to:
3741 1/ carry the number of sibling parms (NUM_PARMS) of the template
3742 parm represented by I.
3744 2/ replace all references to template parm types declared before I
3745 (in the same template parm list as I) by references to template
3746 parm types contained in ARGS. ARGS should contain the list of
3747 template parms that have been fixed up so far, in a form suitable
3748 to be passed to tsubst.
3750 This is a subroutine of fixup_template_parms. */
3753 fixup_template_parm_index (tree i, tree args, int num_parms)
3755 tree index, decl, type;
3758 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3759 /* Do not fix up the index twice. */
3760 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3763 decl = TEMPLATE_PARM_DECL (i);
3764 type = TREE_TYPE (decl);
3766 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3767 TEMPLATE_PARM_LEVEL (i),
3768 TEMPLATE_PARM_ORIG_LEVEL (i),
3772 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3773 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3775 type = tsubst (type, args, tf_none, NULL_TREE);
3777 TREE_TYPE (decl) = type;
3778 TREE_TYPE (index) = type;
3784 This is a subroutine of fixup_template_parms.
3786 It computes the canonical type of the type of the template
3787 parameter PARM_DESC and update all references to that type so that
3788 they use the newly computed canonical type. No access check is
3789 performed during the fixup. PARM_DESC is a TREE_LIST which
3790 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3791 default argument of the template parm if any. IDX is the index of
3792 the template parameter, starting at 0. NUM_PARMS is the number of
3793 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3794 TREE_VEC containing the full set of template parameters in a form
3795 suitable to be passed to substs functions as their ARGS
3796 argument. This is what current_template_args returns for a given
3797 template. The innermost vector of args in ARGLIST is the set of
3798 template parms that have been fixed up so far. This function adds
3799 the fixed up parameter into that vector. */
3802 fixup_template_parm (tree parm_desc,
3807 tree parm = TREE_VALUE (parm_desc);
3808 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3810 push_deferring_access_checks (dk_no_check);
3812 if (TREE_CODE (parm) == TYPE_DECL)
3814 /* PARM is a template type parameter. Fix up its type, add
3815 the fixed-up template parm to the vector of fixed-up
3816 template parms so far, and substitute the fixed-up
3817 template parms into the default argument of this
3820 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3821 TREE_TYPE (parm) = t;
3823 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3825 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3827 /* PARM is a template template parameter. This is going to
3829 tree tparms, targs, innermost_args, t;
3832 /* First, fix up the parms of the template template parm
3833 because the parms are involved in defining the new canonical
3834 type of the template template parm. */
3836 /* So we need to substitute the template parm types that have
3837 been fixed up so far into the template parms of this template
3838 template parm. E.g, consider this:
3840 template<class T, template<T u> class TT> class S;
3842 In this case we want to substitute T into the
3843 template parameters of TT.
3845 So let's walk the template parms of PARM here, and
3846 tsubst ARGLIST into into each of the template
3849 /* For this substitution we need to build the full set of
3850 template parameters and use that as arguments for the
3851 tsubsting function. */
3852 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3854 /* This will contain the innermost parms of PARM into which
3855 we have substituted so far. */
3856 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3857 targs = add_to_template_args (arglist, innermost_args);
3858 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3862 parameter = TREE_VEC_ELT (tparms, j);
3864 /* INNERMOST_ARGS needs to have at least the same number
3865 of elements as the index PARAMETER, ortherwise
3866 tsubsting into PARAMETER will result in partially
3867 instantiating it, reducing its tempate parm
3868 level. Let's tactically fill INNERMOST_ARGS for that
3870 TREE_VEC_ELT (innermost_args, j) =
3871 template_parm_to_arg (parameter);
3873 fixup_template_parm (parameter, j,
3874 TREE_VEC_LENGTH (tparms),
3878 /* Now fix up the type of the template template parm. */
3880 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3881 TREE_TYPE (parm) = t;
3883 TREE_VEC_ELT (fixedup_args, idx) =
3884 template_parm_to_arg (parm_desc);
3886 else if (TREE_CODE (parm) == PARM_DECL)
3888 /* PARM is a non-type template parameter. We need to:
3890 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3891 proper number of sibling parameters.
3893 * Make lookups of the template parameter return a reference
3894 to the fixed-up index. No lookup should return references
3895 to the former index anymore.
3897 * Substitute the template parms that got fixed up so far
3899 * into the type of PARM. */
3901 tree index = DECL_INITIAL (parm);
3903 /* PUSHED_DECL is the decl added to the symbol table with
3904 the name of the parameter. E,g:
3906 template<class T, T u> //#0
3907 auto my_function(T t) -> decltype(u); //#1
3909 Here, when looking up u at //#1, we get the decl of u
3910 resulting from the declaration in #0. This is what
3911 PUSHED_DECL is. We need to replace the reference to the
3912 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3913 fixed-up TEMPLATE_PARM_INDEX. */
3914 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3916 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3917 fixup the type of PUSHED_DECL as well and luckily
3918 fixup_template_parm_index does it for us too. */
3919 tree fixed_up_index =
3920 fixup_template_parm_index (index, arglist, num_parms);
3922 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3924 /* Add this fixed up PARM to the template parms we've fixed
3925 up so far and use that to substitute the fixed-up
3926 template parms into the type of PARM. */
3927 TREE_VEC_ELT (fixedup_args, idx) =
3928 template_parm_to_arg (parm_desc);
3929 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3930 tf_none, NULL_TREE);
3933 TREE_PURPOSE (parm_desc) =
3934 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3935 arglist, tf_none, parm);
3937 pop_deferring_access_checks ();
3940 /* Walk the current template parms and properly compute the canonical
3941 types of the dependent types created during
3942 cp_parser_template_parameter_list. */
3945 fixup_template_parms (void)
3952 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3953 if (parameter_vec == NULL_TREE)
3956 num_parms = TREE_VEC_LENGTH (parameter_vec);
3958 /* This vector contains the current innermost template parms that
3959 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3960 to be passed to tsubst* functions as their ARGS argument. */
3961 fixedup_args = make_tree_vec (num_parms);
3963 /* This vector contains the full set of template parms in a form
3964 suitable to be passed to substs functions as their ARGS
3966 arglist = current_template_args ();
3967 arglist = add_outermost_template_args (arglist, fixedup_args);
3969 /* Let's do the proper fixup now. */
3970 for (i = 0; i < num_parms; ++i)
3971 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3972 i, num_parms, arglist);
3975 /* end_template_decl is called after a template declaration is seen. */
3978 end_template_decl (void)
3980 reset_specialization ();
3982 if (! processing_template_decl)
3985 /* This matches the pushlevel in begin_template_parm_list. */
3988 --processing_template_decl;
3989 current_template_parms = TREE_CHAIN (current_template_parms);
3992 /* Takes a TREE_LIST representing a template parameter and convert it
3993 into an argument suitable to be passed to the type substitution
3994 functions. Note that If the TREE_LIST contains an error_mark
3995 node, the returned argument is error_mark_node. */
3998 template_parm_to_arg (tree t)
4002 || TREE_CODE (t) != TREE_LIST)
4005 if (error_operand_p (TREE_VALUE (t)))
4006 return error_mark_node;
4010 if (TREE_CODE (t) == TYPE_DECL
4011 || TREE_CODE (t) == TEMPLATE_DECL)
4015 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
4017 /* Turn this argument into a TYPE_ARGUMENT_PACK
4018 with a single element, which expands T. */
4019 tree vec = make_tree_vec (1);
4020 #ifdef ENABLE_CHECKING
4021 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4022 (vec, TREE_VEC_LENGTH (vec));
4024 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4026 t = cxx_make_type (TYPE_ARGUMENT_PACK);
4027 SET_ARGUMENT_PACK_ARGS (t, vec);
4032 t = DECL_INITIAL (t);
4034 if (TEMPLATE_PARM_PARAMETER_PACK (t))
4036 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
4037 with a single element, which expands T. */
4038 tree vec = make_tree_vec (1);
4039 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
4040 #ifdef ENABLE_CHECKING
4041 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4042 (vec, TREE_VEC_LENGTH (vec));
4044 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4046 t = make_node (NONTYPE_ARGUMENT_PACK);
4047 SET_ARGUMENT_PACK_ARGS (t, vec);
4048 TREE_TYPE (t) = type;
4054 /* This function returns TRUE if PARM_PACK is a template parameter
4055 pack and if ARG_PACK is what template_parm_to_arg returned when
4056 passed PARM_PACK. */
4059 arg_from_parm_pack_p (tree arg_pack, tree parm_pack)
4061 /* For clarity in the comments below let's use the representation
4062 argument_pack<elements>' to denote an argument pack and its
4065 In the 'if' block below, we want to detect cases where
4066 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
4067 check if ARG_PACK is an argument pack which sole element is
4068 the expansion of PARM_PACK. That argument pack is typically
4069 created by template_parm_to_arg when passed a parameter
4073 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
4074 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
4076 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
4077 tree pattern = PACK_EXPANSION_PATTERN (expansion);
4078 /* So we have an argument_pack<P...>. We want to test if P
4079 is actually PARM_PACK. We will not use cp_tree_equal to
4080 test P and PARM_PACK because during type fixup (by
4081 fixup_template_parm) P can be a pre-fixup version of a
4082 type and PARM_PACK be its post-fixup version.
4083 cp_tree_equal would consider them as different even
4084 though we would want to consider them compatible for our
4085 precise purpose here.
4087 Thus we are going to consider that P and PARM_PACK are
4088 compatible if they have the same DECL. */
4089 if ((/* If ARG_PACK is a type parameter pack named by the
4090 same DECL as parm_pack ... */
4092 && TYPE_P (parm_pack)
4093 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
4094 /* ... or if PARM_PACK is a non-type parameter named by the
4095 same DECL as ARG_PACK. Note that PARM_PACK being a
4096 non-type parameter means it's either a PARM_DECL or a
4097 TEMPLATE_PARM_INDEX. */
4098 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
4099 && ((TREE_CODE (parm_pack) == PARM_DECL
4100 && (TEMPLATE_PARM_DECL (pattern)
4101 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
4102 || (TREE_CODE (parm_pack) == TEMPLATE_PARM_INDEX
4103 && (TEMPLATE_PARM_DECL (pattern)
4104 == TEMPLATE_PARM_DECL (parm_pack))))))
4105 && template_parameter_pack_p (pattern))
4111 /* Within the declaration of a template, return all levels of template
4112 parameters that apply. The template parameters are represented as
4113 a TREE_VEC, in the form documented in cp-tree.h for template
4117 current_template_args (void)
4120 tree args = NULL_TREE;
4121 int length = TMPL_PARMS_DEPTH (current_template_parms);
4124 /* If there is only one level of template parameters, we do not
4125 create a TREE_VEC of TREE_VECs. Instead, we return a single
4126 TREE_VEC containing the arguments. */
4128 args = make_tree_vec (length);
4130 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4132 tree a = copy_node (TREE_VALUE (header));
4135 TREE_TYPE (a) = NULL_TREE;
4136 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4137 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4139 #ifdef ENABLE_CHECKING
4140 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4144 TREE_VEC_ELT (args, --l) = a;
4149 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4150 /* This can happen for template parms of a template template
4153 template<template<class T, class U> class TT> struct S;
4155 Consider the level of the parms of TT; T and U both have
4156 level 2; TT has no template parm of level 1. So in this case
4157 the first element of full_template_args is NULL_TREE. If we
4158 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4159 of 2. This will make tsubst wrongly consider that T and U
4160 have level 1. Instead, let's create a dummy vector as the
4161 first element of full_template_args so that TMPL_ARG_DEPTH
4162 returns the correct depth for args. */
4163 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4167 /* Update the declared TYPE by doing any lookups which were thought to be
4168 dependent, but are not now that we know the SCOPE of the declarator. */
4171 maybe_update_decl_type (tree orig_type, tree scope)
4173 tree type = orig_type;
4175 if (type == NULL_TREE)
4178 if (TREE_CODE (orig_type) == TYPE_DECL)
4179 type = TREE_TYPE (type);
4181 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4182 && dependent_type_p (type)
4183 /* Don't bother building up the args in this case. */
4184 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4186 /* tsubst in the args corresponding to the template parameters,
4187 including auto if present. Most things will be unchanged, but
4188 make_typename_type and tsubst_qualified_id will resolve
4189 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4190 tree args = current_template_args ();
4191 tree auto_node = type_uses_auto (type);
4195 tree auto_vec = make_tree_vec (1);
4196 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4197 args = add_to_template_args (args, auto_vec);
4199 pushed = push_scope (scope);
4200 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4205 if (type == error_mark_node)
4208 if (TREE_CODE (orig_type) == TYPE_DECL)
4210 if (same_type_p (type, TREE_TYPE (orig_type)))
4213 type = TYPE_NAME (type);
4218 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4219 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4220 a member template. Used by push_template_decl below. */
4223 build_template_decl (tree decl, tree parms, bool member_template_p)
4225 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4226 DECL_TEMPLATE_PARMS (tmpl) = parms;
4227 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4228 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
4229 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4234 struct template_parm_data
4236 /* The level of the template parameters we are currently
4240 /* The index of the specialization argument we are currently
4244 /* An array whose size is the number of template parameters. The
4245 elements are nonzero if the parameter has been used in any one
4246 of the arguments processed so far. */
4249 /* An array whose size is the number of template arguments. The
4250 elements are nonzero if the argument makes use of template
4251 parameters of this level. */
4252 int* arg_uses_template_parms;
4255 /* Subroutine of push_template_decl used to see if each template
4256 parameter in a partial specialization is used in the explicit
4257 argument list. If T is of the LEVEL given in DATA (which is
4258 treated as a template_parm_data*), then DATA->PARMS is marked
4262 mark_template_parm (tree t, void* data)
4266 struct template_parm_data* tpd = (struct template_parm_data*) data;
4268 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4270 level = TEMPLATE_PARM_LEVEL (t);
4271 idx = TEMPLATE_PARM_IDX (t);
4275 level = TEMPLATE_TYPE_LEVEL (t);
4276 idx = TEMPLATE_TYPE_IDX (t);
4279 if (level == tpd->level)
4281 tpd->parms[idx] = 1;
4282 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4285 /* Return zero so that for_each_template_parm will continue the
4286 traversal of the tree; we want to mark *every* template parm. */
4290 /* Process the partial specialization DECL. */
4293 process_partial_specialization (tree decl)
4295 tree type = TREE_TYPE (decl);
4296 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4297 tree specargs = CLASSTYPE_TI_ARGS (type);
4298 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4299 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4302 int nargs = TREE_VEC_LENGTH (inner_args);
4305 bool did_error_intro = false;
4306 struct template_parm_data tpd;
4307 struct template_parm_data tpd2;
4309 gcc_assert (current_template_parms);
4311 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4312 ntparms = TREE_VEC_LENGTH (inner_parms);
4314 /* We check that each of the template parameters given in the
4315 partial specialization is used in the argument list to the
4316 specialization. For example:
4318 template <class T> struct S;
4319 template <class T> struct S<T*>;
4321 The second declaration is OK because `T*' uses the template
4322 parameter T, whereas
4324 template <class T> struct S<int>;
4326 is no good. Even trickier is:
4337 The S2<T> declaration is actually invalid; it is a
4338 full-specialization. Of course,
4341 struct S2<T (*)(U)>;
4343 or some such would have been OK. */
4344 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4345 tpd.parms = XALLOCAVEC (int, ntparms);
4346 memset (tpd.parms, 0, sizeof (int) * ntparms);
4348 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4349 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4350 for (i = 0; i < nargs; ++i)
4352 tpd.current_arg = i;
4353 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4354 &mark_template_parm,
4357 /*include_nondeduced_p=*/false);
4359 for (i = 0; i < ntparms; ++i)
4360 if (tpd.parms[i] == 0)
4362 /* One of the template parms was not used in the
4364 if (!did_error_intro)
4366 error ("template parameters not used in partial specialization:");
4367 did_error_intro = true;
4370 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4373 if (did_error_intro)
4374 return error_mark_node;
4376 /* [temp.class.spec]
4378 The argument list of the specialization shall not be identical to
4379 the implicit argument list of the primary template. */
4380 if (comp_template_args
4382 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4384 error ("partial specialization %qT does not specialize any template arguments", type);
4386 /* [temp.class.spec]
4388 A partially specialized non-type argument expression shall not
4389 involve template parameters of the partial specialization except
4390 when the argument expression is a simple identifier.
4392 The type of a template parameter corresponding to a specialized
4393 non-type argument shall not be dependent on a parameter of the
4396 Also, we verify that pack expansions only occur at the
4397 end of the argument list. */
4398 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4400 for (i = 0; i < nargs; ++i)
4402 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4403 tree arg = TREE_VEC_ELT (inner_args, i);
4404 tree packed_args = NULL_TREE;
4407 if (ARGUMENT_PACK_P (arg))
4409 /* Extract the arguments from the argument pack. We'll be
4410 iterating over these in the following loop. */
4411 packed_args = ARGUMENT_PACK_ARGS (arg);
4412 len = TREE_VEC_LENGTH (packed_args);
4415 for (j = 0; j < len; j++)
4418 /* Get the Jth argument in the parameter pack. */
4419 arg = TREE_VEC_ELT (packed_args, j);
4421 if (PACK_EXPANSION_P (arg))
4423 /* Pack expansions must come at the end of the
4425 if ((packed_args && j < len - 1)
4426 || (!packed_args && i < nargs - 1))
4428 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4429 error ("parameter pack argument %qE must be at the "
4430 "end of the template argument list", arg);
4432 error ("parameter pack argument %qT must be at the "
4433 "end of the template argument list", arg);
4437 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4438 /* We only care about the pattern. */
4439 arg = PACK_EXPANSION_PATTERN (arg);
4441 if (/* These first two lines are the `non-type' bit. */
4443 && TREE_CODE (arg) != TEMPLATE_DECL
4444 /* This next line is the `argument expression is not just a
4445 simple identifier' condition and also the `specialized
4446 non-type argument' bit. */
4447 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4449 if ((!packed_args && tpd.arg_uses_template_parms[i])
4450 || (packed_args && uses_template_parms (arg)))
4451 error ("template argument %qE involves template parameter(s)",
4455 /* Look at the corresponding template parameter,
4456 marking which template parameters its type depends
4458 tree type = TREE_TYPE (parm);
4462 /* We haven't yet initialized TPD2. Do so now. */
4463 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4464 /* The number of parameters here is the number in the
4465 main template, which, as checked in the assertion
4467 tpd2.parms = XALLOCAVEC (int, nargs);
4469 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4472 /* Mark the template parameters. But this time, we're
4473 looking for the template parameters of the main
4474 template, not in the specialization. */
4475 tpd2.current_arg = i;
4476 tpd2.arg_uses_template_parms[i] = 0;
4477 memset (tpd2.parms, 0, sizeof (int) * nargs);
4478 for_each_template_parm (type,
4479 &mark_template_parm,
4482 /*include_nondeduced_p=*/false);
4484 if (tpd2.arg_uses_template_parms [i])
4486 /* The type depended on some template parameters.
4487 If they are fully specialized in the
4488 specialization, that's OK. */
4491 for (j = 0; j < nargs; ++j)
4492 if (tpd2.parms[j] != 0
4493 && tpd.arg_uses_template_parms [j])
4496 error_n (input_location, count,
4497 "type %qT of template argument %qE depends "
4498 "on a template parameter",
4499 "type %qT of template argument %qE depends "
4500 "on template parameters",
4509 /* We should only get here once. */
4510 gcc_assert (!COMPLETE_TYPE_P (type));
4512 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4513 = tree_cons (specargs, inner_parms,
4514 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4515 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4517 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4518 inst = TREE_CHAIN (inst))
4520 tree inst_type = TREE_VALUE (inst);
4521 if (COMPLETE_TYPE_P (inst_type)
4522 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4524 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4525 if (spec && TREE_TYPE (spec) == type)
4526 permerror (input_location,
4527 "partial specialization of %qT after instantiation "
4528 "of %qT", type, inst_type);
4535 /* Check that a template declaration's use of default arguments and
4536 parameter packs is not invalid. Here, PARMS are the template
4537 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4538 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4542 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4543 declaration (but not a definition); 1 indicates a declaration, 2
4544 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4545 emitted for extraneous default arguments.
4547 Returns TRUE if there were no errors found, FALSE otherwise. */
4550 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4551 int is_partial, int is_friend_decl)
4554 int last_level_to_check;
4556 bool no_errors = true;
4560 A default template-argument shall not be specified in a
4561 function template declaration or a function template definition, nor
4562 in the template-parameter-list of the definition of a member of a
4565 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4566 /* You can't have a function template declaration in a local
4567 scope, nor you can you define a member of a class template in a
4571 if (current_class_type
4572 && !TYPE_BEING_DEFINED (current_class_type)
4573 && DECL_LANG_SPECIFIC (decl)
4574 && DECL_DECLARES_FUNCTION_P (decl)
4575 /* If this is either a friend defined in the scope of the class
4576 or a member function. */
4577 && (DECL_FUNCTION_MEMBER_P (decl)
4578 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4579 : DECL_FRIEND_CONTEXT (decl)
4580 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4582 /* And, if it was a member function, it really was defined in
4583 the scope of the class. */
4584 && (!DECL_FUNCTION_MEMBER_P (decl)
4585 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4586 /* We already checked these parameters when the template was
4587 declared, so there's no need to do it again now. This function
4588 was defined in class scope, but we're processing it's body now
4589 that the class is complete. */
4592 /* Core issue 226 (C++0x only): the following only applies to class
4594 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4598 If a template-parameter has a default template-argument, all
4599 subsequent template-parameters shall have a default
4600 template-argument supplied. */
4601 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4603 tree inner_parms = TREE_VALUE (parm_level);
4604 int ntparms = TREE_VEC_LENGTH (inner_parms);
4605 int seen_def_arg_p = 0;
4608 for (i = 0; i < ntparms; ++i)
4610 tree parm = TREE_VEC_ELT (inner_parms, i);
4612 if (parm == error_mark_node)
4615 if (TREE_PURPOSE (parm))
4617 else if (seen_def_arg_p
4618 && !template_parameter_pack_p (TREE_VALUE (parm)))
4620 error ("no default argument for %qD", TREE_VALUE (parm));
4621 /* For better subsequent error-recovery, we indicate that
4622 there should have been a default argument. */
4623 TREE_PURPOSE (parm) = error_mark_node;
4629 /* Don't complain about an enclosing partial
4631 && parm_level == parms
4632 && TREE_CODE (decl) == TYPE_DECL
4634 && template_parameter_pack_p (TREE_VALUE (parm)))
4636 /* A primary class template can only have one
4637 parameter pack, at the end of the template
4640 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4641 error ("parameter pack %qE must be at the end of the"
4642 " template parameter list", TREE_VALUE (parm));
4644 error ("parameter pack %qT must be at the end of the"
4645 " template parameter list",
4646 TREE_TYPE (TREE_VALUE (parm)));
4648 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4656 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4660 /* For an ordinary class template, default template arguments are
4661 allowed at the innermost level, e.g.:
4662 template <class T = int>
4664 but, in a partial specialization, they're not allowed even
4665 there, as we have in [temp.class.spec]:
4667 The template parameter list of a specialization shall not
4668 contain default template argument values.
4670 So, for a partial specialization, or for a function template
4671 (in C++98/C++03), we look at all of them. */
4674 /* But, for a primary class template that is not a partial
4675 specialization we look at all template parameters except the
4677 parms = TREE_CHAIN (parms);
4679 /* Figure out what error message to issue. */
4680 if (is_friend_decl == 2)
4681 msg = G_("default template arguments may not be used in function template "
4682 "friend re-declaration");
4683 else if (is_friend_decl)
4684 msg = G_("default template arguments may not be used in function template "
4685 "friend declarations");
4686 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4687 msg = G_("default template arguments may not be used in function templates "
4688 "without -std=c++11 or -std=gnu++11");
4689 else if (is_partial)
4690 msg = G_("default template arguments may not be used in "
4691 "partial specializations");
4693 msg = G_("default argument for template parameter for class enclosing %qD");
4695 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4696 /* If we're inside a class definition, there's no need to
4697 examine the parameters to the class itself. On the one
4698 hand, they will be checked when the class is defined, and,
4699 on the other, default arguments are valid in things like:
4700 template <class T = double>
4701 struct S { template <class U> void f(U); };
4702 Here the default argument for `S' has no bearing on the
4703 declaration of `f'. */
4704 last_level_to_check = template_class_depth (current_class_type) + 1;
4706 /* Check everything. */
4707 last_level_to_check = 0;
4709 for (parm_level = parms;
4710 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4711 parm_level = TREE_CHAIN (parm_level))
4713 tree inner_parms = TREE_VALUE (parm_level);
4717 ntparms = TREE_VEC_LENGTH (inner_parms);
4718 for (i = 0; i < ntparms; ++i)
4720 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4723 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4728 if (is_friend_decl == 2)
4735 /* Clear out the default argument so that we are not
4737 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4741 /* At this point, if we're still interested in issuing messages,
4742 they must apply to classes surrounding the object declared. */
4744 msg = G_("default argument for template parameter for class "
4751 /* Worker for push_template_decl_real, called via
4752 for_each_template_parm. DATA is really an int, indicating the
4753 level of the parameters we are interested in. If T is a template
4754 parameter of that level, return nonzero. */
4757 template_parm_this_level_p (tree t, void* data)
4759 int this_level = *(int *)data;
4762 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4763 level = TEMPLATE_PARM_LEVEL (t);
4765 level = TEMPLATE_TYPE_LEVEL (t);
4766 return level == this_level;
4769 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4770 parameters given by current_template_args, or reuses a
4771 previously existing one, if appropriate. Returns the DECL, or an
4772 equivalent one, if it is replaced via a call to duplicate_decls.
4774 If IS_FRIEND is true, DECL is a friend declaration. */
4777 push_template_decl_real (tree decl, bool is_friend)
4785 int new_template_p = 0;
4786 /* True if the template is a member template, in the sense of
4788 bool member_template_p = false;
4790 if (decl == error_mark_node || !current_template_parms)
4791 return error_mark_node;
4793 /* See if this is a partial specialization. */
4794 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4795 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4796 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4798 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4802 /* For a friend, we want the context of the friend function, not
4803 the type of which it is a friend. */
4804 ctx = CP_DECL_CONTEXT (decl);
4805 else if (CP_DECL_CONTEXT (decl)
4806 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4807 /* In the case of a virtual function, we want the class in which
4809 ctx = CP_DECL_CONTEXT (decl);
4811 /* Otherwise, if we're currently defining some class, the DECL
4812 is assumed to be a member of the class. */
4813 ctx = current_scope ();
4815 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4818 if (!DECL_CONTEXT (decl))
4819 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4821 /* See if this is a primary template. */
4822 if (is_friend && ctx)
4823 /* A friend template that specifies a class context, i.e.
4824 template <typename T> friend void A<T>::f();
4828 primary = template_parm_scope_p ();
4832 if (DECL_CLASS_SCOPE_P (decl))
4833 member_template_p = true;
4834 if (TREE_CODE (decl) == TYPE_DECL
4835 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4837 error ("template class without a name");
4838 return error_mark_node;
4840 else if (TREE_CODE (decl) == FUNCTION_DECL)
4842 if (DECL_DESTRUCTOR_P (decl))
4846 A destructor shall not be a member template. */
4847 error ("destructor %qD declared as member template", decl);
4848 return error_mark_node;
4850 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4851 && (!prototype_p (TREE_TYPE (decl))
4852 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4853 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4854 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4855 == void_list_node)))
4857 /* [basic.stc.dynamic.allocation]
4859 An allocation function can be a function
4860 template. ... Template allocation functions shall
4861 have two or more parameters. */
4862 error ("invalid template declaration of %qD", decl);
4863 return error_mark_node;
4866 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4867 && CLASS_TYPE_P (TREE_TYPE (decl)))
4869 else if (TREE_CODE (decl) == TYPE_DECL
4870 && TYPE_DECL_ALIAS_P (decl))
4871 /* alias-declaration */
4872 gcc_assert (!DECL_ARTIFICIAL (decl));
4875 error ("template declaration of %q#D", decl);
4876 return error_mark_node;
4880 /* Check to see that the rules regarding the use of default
4881 arguments are not being violated. */
4882 check_default_tmpl_args (decl, current_template_parms,
4883 primary, is_partial, /*is_friend_decl=*/0);
4885 /* Ensure that there are no parameter packs in the type of this
4886 declaration that have not been expanded. */
4887 if (TREE_CODE (decl) == FUNCTION_DECL)
4889 /* Check each of the arguments individually to see if there are
4890 any bare parameter packs. */
4891 tree type = TREE_TYPE (decl);
4892 tree arg = DECL_ARGUMENTS (decl);
4893 tree argtype = TYPE_ARG_TYPES (type);
4895 while (arg && argtype)
4897 if (!FUNCTION_PARAMETER_PACK_P (arg)
4898 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4900 /* This is a PARM_DECL that contains unexpanded parameter
4901 packs. We have already complained about this in the
4902 check_for_bare_parameter_packs call, so just replace
4903 these types with ERROR_MARK_NODE. */
4904 TREE_TYPE (arg) = error_mark_node;
4905 TREE_VALUE (argtype) = error_mark_node;
4908 arg = DECL_CHAIN (arg);
4909 argtype = TREE_CHAIN (argtype);
4912 /* Check for bare parameter packs in the return type and the
4913 exception specifiers. */
4914 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4915 /* Errors were already issued, set return type to int
4916 as the frontend doesn't expect error_mark_node as
4918 TREE_TYPE (type) = integer_type_node;
4919 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4920 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4922 else if (check_for_bare_parameter_packs ((TREE_CODE (decl) == TYPE_DECL
4923 && TYPE_DECL_ALIAS_P (decl))
4924 ? DECL_ORIGINAL_TYPE (decl)
4925 : TREE_TYPE (decl)))
4927 TREE_TYPE (decl) = error_mark_node;
4928 return error_mark_node;
4932 return process_partial_specialization (decl);
4934 args = current_template_args ();
4937 || TREE_CODE (ctx) == FUNCTION_DECL
4938 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4939 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4941 if (DECL_LANG_SPECIFIC (decl)
4942 && DECL_TEMPLATE_INFO (decl)
4943 && DECL_TI_TEMPLATE (decl))
4944 tmpl = DECL_TI_TEMPLATE (decl);
4945 /* If DECL is a TYPE_DECL for a class-template, then there won't
4946 be DECL_LANG_SPECIFIC. The information equivalent to
4947 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4948 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4949 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4950 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4952 /* Since a template declaration already existed for this
4953 class-type, we must be redeclaring it here. Make sure
4954 that the redeclaration is valid. */
4955 redeclare_class_template (TREE_TYPE (decl),
4956 current_template_parms);
4957 /* We don't need to create a new TEMPLATE_DECL; just use the
4958 one we already had. */
4959 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4963 tmpl = build_template_decl (decl, current_template_parms,
4967 if (DECL_LANG_SPECIFIC (decl)
4968 && DECL_TEMPLATE_SPECIALIZATION (decl))
4970 /* A specialization of a member template of a template
4972 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4973 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4974 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4980 tree a, t, current, parms;
4982 tree tinfo = get_template_info (decl);
4986 error ("template definition of non-template %q#D", decl);
4987 return error_mark_node;
4990 tmpl = TI_TEMPLATE (tinfo);
4992 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4993 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4994 && DECL_TEMPLATE_SPECIALIZATION (decl)
4995 && DECL_MEMBER_TEMPLATE_P (tmpl))
4999 /* The declaration is a specialization of a member
5000 template, declared outside the class. Therefore, the
5001 innermost template arguments will be NULL, so we
5002 replace them with the arguments determined by the
5003 earlier call to check_explicit_specialization. */
5004 args = DECL_TI_ARGS (decl);
5007 = build_template_decl (decl, current_template_parms,
5009 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
5010 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
5011 DECL_TI_TEMPLATE (decl) = new_tmpl;
5012 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
5013 DECL_TEMPLATE_INFO (new_tmpl)
5014 = build_template_info (tmpl, args);
5016 register_specialization (new_tmpl,
5017 most_general_template (tmpl),
5023 /* Make sure the template headers we got make sense. */
5025 parms = DECL_TEMPLATE_PARMS (tmpl);
5026 i = TMPL_PARMS_DEPTH (parms);
5027 if (TMPL_ARGS_DEPTH (args) != i)
5029 error ("expected %d levels of template parms for %q#D, got %d",
5030 i, decl, TMPL_ARGS_DEPTH (args));
5033 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
5035 a = TMPL_ARGS_LEVEL (args, i);
5036 t = INNERMOST_TEMPLATE_PARMS (parms);
5038 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
5040 if (current == decl)
5041 error ("got %d template parameters for %q#D",
5042 TREE_VEC_LENGTH (a), decl);
5044 error ("got %d template parameters for %q#T",
5045 TREE_VEC_LENGTH (a), current);
5046 error (" but %d required", TREE_VEC_LENGTH (t));
5047 return error_mark_node;
5050 if (current == decl)
5052 else if (current == NULL_TREE)
5053 /* Can happen in erroneous input. */
5056 current = (TYPE_P (current)
5057 ? TYPE_CONTEXT (current)
5058 : DECL_CONTEXT (current));
5061 /* Check that the parms are used in the appropriate qualifying scopes
5062 in the declarator. */
5063 if (!comp_template_args
5065 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
5068 template arguments to %qD do not match original template %qD",
5069 decl, DECL_TEMPLATE_RESULT (tmpl));
5070 if (!uses_template_parms (TI_ARGS (tinfo)))
5071 inform (input_location, "use template<> for an explicit specialization");
5072 /* Avoid crash in import_export_decl. */
5073 DECL_INTERFACE_KNOWN (decl) = 1;
5074 return error_mark_node;
5078 DECL_TEMPLATE_RESULT (tmpl) = decl;
5079 TREE_TYPE (tmpl) = TREE_TYPE (decl);
5081 /* Push template declarations for global functions and types. Note
5082 that we do not try to push a global template friend declared in a
5083 template class; such a thing may well depend on the template
5084 parameters of the class. */
5085 if (new_template_p && !ctx
5086 && !(is_friend && template_class_depth (current_class_type) > 0))
5088 tmpl = pushdecl_namespace_level (tmpl, is_friend);
5089 if (tmpl == error_mark_node)
5090 return error_mark_node;
5092 /* Hide template friend classes that haven't been declared yet. */
5093 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
5095 DECL_ANTICIPATED (tmpl) = 1;
5096 DECL_FRIEND_P (tmpl) = 1;
5102 tree parms = DECL_TEMPLATE_PARMS (tmpl);
5105 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
5106 if (DECL_CONV_FN_P (tmpl))
5108 int depth = TMPL_PARMS_DEPTH (parms);
5110 /* It is a conversion operator. See if the type converted to
5111 depends on innermost template operands. */
5113 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
5115 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
5118 /* Give template template parms a DECL_CONTEXT of the template
5119 for which they are a parameter. */
5120 parms = INNERMOST_TEMPLATE_PARMS (parms);
5121 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5123 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5124 if (TREE_CODE (parm) == TEMPLATE_DECL)
5125 DECL_CONTEXT (parm) = tmpl;
5129 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5130 back to its most general template. If TMPL is a specialization,
5131 ARGS may only have the innermost set of arguments. Add the missing
5132 argument levels if necessary. */
5133 if (DECL_TEMPLATE_INFO (tmpl))
5134 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5136 info = build_template_info (tmpl, args);
5138 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5139 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5142 if (primary && !DECL_LANG_SPECIFIC (decl))
5143 retrofit_lang_decl (decl);
5144 if (DECL_LANG_SPECIFIC (decl))
5145 DECL_TEMPLATE_INFO (decl) = info;
5148 return DECL_TEMPLATE_RESULT (tmpl);
5152 push_template_decl (tree decl)
5154 return push_template_decl_real (decl, false);
5157 /* Called when a class template TYPE is redeclared with the indicated
5158 template PARMS, e.g.:
5160 template <class T> struct S;
5161 template <class T> struct S {}; */
5164 redeclare_class_template (tree type, tree parms)
5170 if (!TYPE_TEMPLATE_INFO (type))
5172 error ("%qT is not a template type", type);
5176 tmpl = TYPE_TI_TEMPLATE (type);
5177 if (!PRIMARY_TEMPLATE_P (tmpl))
5178 /* The type is nested in some template class. Nothing to worry
5179 about here; there are no new template parameters for the nested
5185 error ("template specifiers not specified in declaration of %qD",
5190 parms = INNERMOST_TEMPLATE_PARMS (parms);
5191 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5193 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5195 error_n (input_location, TREE_VEC_LENGTH (parms),
5196 "redeclared with %d template parameter",
5197 "redeclared with %d template parameters",
5198 TREE_VEC_LENGTH (parms));
5199 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5200 "previous declaration %q+D used %d template parameter",
5201 "previous declaration %q+D used %d template parameters",
5202 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5206 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5213 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5214 || TREE_VEC_ELT (parms, i) == error_mark_node)
5217 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5218 if (tmpl_parm == error_mark_node)
5221 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5222 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5223 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5225 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5227 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5228 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5229 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5230 || (TREE_CODE (tmpl_parm) != PARM_DECL
5231 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5232 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5233 || (TREE_CODE (tmpl_parm) == PARM_DECL
5234 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5235 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5237 error ("template parameter %q+#D", tmpl_parm);
5238 error ("redeclared here as %q#D", parm);
5242 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5244 /* We have in [temp.param]:
5246 A template-parameter may not be given default arguments
5247 by two different declarations in the same scope. */
5248 error_at (input_location, "redefinition of default argument for %q#D", parm);
5249 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5250 "original definition appeared here");
5254 if (parm_default != NULL_TREE)
5255 /* Update the previous template parameters (which are the ones
5256 that will really count) with the new default value. */
5257 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5258 else if (tmpl_default != NULL_TREE)
5259 /* Update the new parameters, too; they'll be used as the
5260 parameters for any members. */
5261 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5267 /* Simplify EXPR if it is a non-dependent expression. Returns the
5268 (possibly simplified) expression. */
5271 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5273 if (expr == NULL_TREE)
5276 /* If we're in a template, but EXPR isn't value dependent, simplify
5277 it. We're supposed to treat:
5279 template <typename T> void f(T[1 + 1]);
5280 template <typename T> void f(T[2]);
5282 as two declarations of the same function, for example. */
5283 if (processing_template_decl
5284 && !type_dependent_expression_p (expr)
5285 && potential_constant_expression (expr)
5286 && !value_dependent_expression_p (expr))
5288 HOST_WIDE_INT saved_processing_template_decl;
5290 saved_processing_template_decl = processing_template_decl;
5291 processing_template_decl = 0;
5292 expr = tsubst_copy_and_build (expr,
5295 /*in_decl=*/NULL_TREE,
5296 /*function_p=*/false,
5297 /*integral_constant_expression_p=*/true);
5298 processing_template_decl = saved_processing_template_decl;
5304 fold_non_dependent_expr (tree expr)
5306 return fold_non_dependent_expr_sfinae (expr, tf_error);
5309 /* Return TRUE iff T is a type alias, a TEMPLATE_DECL for an alias
5310 template declaration, or a TYPE_DECL for an alias declaration. */
5313 alias_type_or_template_p (tree t)
5317 return ((TREE_CODE (t) == TYPE_DECL && TYPE_DECL_ALIAS_P (t))
5320 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
5321 || DECL_ALIAS_TEMPLATE_P (t));
5324 /* Return TRUE iff is a specialization of an alias template. */
5327 alias_template_specialization_p (tree t)
5331 return (primary_template_instantiation_p (t)
5332 && DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (t)));
5335 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5336 must be a function or a pointer-to-function type, as specified
5337 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5338 and check that the resulting function has external linkage. */
5341 convert_nontype_argument_function (tree type, tree expr)
5345 linkage_kind linkage;
5347 fn = instantiate_type (type, fns, tf_none);
5348 if (fn == error_mark_node)
5349 return error_mark_node;
5352 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5353 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5354 if (BASELINK_P (fn_no_ptr))
5355 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5357 /* [temp.arg.nontype]/1
5359 A template-argument for a non-type, non-template template-parameter
5362 -- the address of an object or function with external [C++11: or
5363 internal] linkage. */
5364 linkage = decl_linkage (fn_no_ptr);
5365 if (cxx_dialect >= cxx0x ? linkage == lk_none : linkage != lk_external)
5367 if (cxx_dialect >= cxx0x)
5368 error ("%qE is not a valid template argument for type %qT "
5369 "because %qD has no linkage",
5370 expr, type, fn_no_ptr);
5372 error ("%qE is not a valid template argument for type %qT "
5373 "because %qD does not have external linkage",
5374 expr, type, fn_no_ptr);
5381 /* Subroutine of convert_nontype_argument.
5382 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5383 Emit an error otherwise. */
5386 check_valid_ptrmem_cst_expr (tree type, tree expr,
5387 tsubst_flags_t complain)
5390 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5392 if (cxx_dialect >= cxx0x && null_member_pointer_value_p (expr))
5394 if (complain & tf_error)
5396 error ("%qE is not a valid template argument for type %qT",
5398 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5403 /* Returns TRUE iff the address of OP is value-dependent.
5405 14.6.2.4 [temp.dep.temp]:
5406 A non-integral non-type template-argument is dependent if its type is
5407 dependent or it has either of the following forms
5410 and contains a nested-name-specifier which specifies a class-name that
5411 names a dependent type.
5413 We generalize this to just say that the address of a member of a
5414 dependent class is value-dependent; the above doesn't cover the
5415 address of a static data member named with an unqualified-id. */
5418 has_value_dependent_address (tree op)
5420 /* We could use get_inner_reference here, but there's no need;
5421 this is only relevant for template non-type arguments, which
5422 can only be expressed as &id-expression. */
5425 tree ctx = CP_DECL_CONTEXT (op);
5426 if (TYPE_P (ctx) && dependent_type_p (ctx))
5433 /* The next set of functions are used for providing helpful explanatory
5434 diagnostics for failed overload resolution. Their messages should be
5435 indented by two spaces for consistency with the messages in
5439 unify_success (bool explain_p ATTRIBUTE_UNUSED)
5445 unify_parameter_deduction_failure (bool explain_p, tree parm)
5448 inform (input_location,
5449 " couldn't deduce template parameter %qD", parm);
5454 unify_invalid (bool explain_p ATTRIBUTE_UNUSED)
5460 unify_cv_qual_mismatch (bool explain_p, tree parm, tree arg)
5463 inform (input_location,
5464 " types %qT and %qT have incompatible cv-qualifiers",
5470 unify_type_mismatch (bool explain_p, tree parm, tree arg)
5473 inform (input_location, " mismatched types %qT and %qT", parm, arg);
5478 unify_parameter_pack_mismatch (bool explain_p, tree parm, tree arg)
5481 inform (input_location,
5482 " template parameter %qD is not a parameter pack, but "
5489 unify_ptrmem_cst_mismatch (bool explain_p, tree parm, tree arg)
5492 inform (input_location,
5493 " template argument %qE does not match "
5494 "pointer-to-member constant %qE",
5500 unify_expression_unequal (bool explain_p, tree parm, tree arg)
5503 inform (input_location, " %qE is not equivalent to %qE", parm, arg);
5508 unify_parameter_pack_inconsistent (bool explain_p, tree old_arg, tree new_arg)
5511 inform (input_location,
5512 " inconsistent parameter pack deduction with %qT and %qT",
5518 unify_inconsistency (bool explain_p, tree parm, tree first, tree second)
5523 inform (input_location,
5524 " deduced conflicting types for parameter %qT (%qT and %qT)",
5525 parm, first, second);
5527 inform (input_location,
5528 " deduced conflicting values for non-type parameter "
5529 "%qE (%qE and %qE)", parm, first, second);
5535 unify_vla_arg (bool explain_p, tree arg)
5538 inform (input_location,
5539 " variable-sized array type %qT is not "
5540 "a valid template argument",
5546 unify_method_type_error (bool explain_p, tree arg)
5549 inform (input_location,
5550 " member function type %qT is not a valid template argument",
5556 unify_arity (bool explain_p, int have, int wanted)
5559 inform_n (input_location, wanted,
5560 " candidate expects %d argument, %d provided",
5561 " candidate expects %d arguments, %d provided",
5567 unify_too_many_arguments (bool explain_p, int have, int wanted)
5569 return unify_arity (explain_p, have, wanted);
5573 unify_too_few_arguments (bool explain_p, int have, int wanted)
5575 return unify_arity (explain_p, have, wanted);
5579 unify_arg_conversion (bool explain_p, tree to_type,
5580 tree from_type, tree arg)
5583 inform (input_location, " cannot convert %qE (type %qT) to type %qT",
5584 arg, from_type, to_type);
5589 unify_no_common_base (bool explain_p, enum template_base_result r,
5590 tree parm, tree arg)
5595 case tbr_ambiguous_baseclass:
5596 inform (input_location, " %qT is an ambiguous base class of %qT",
5600 inform (input_location, " %qT is not derived from %qT", arg, parm);
5607 unify_inconsistent_template_template_parameters (bool explain_p)
5610 inform (input_location,
5611 " template parameters of a template template argument are "
5612 "inconsistent with other deduced template arguments");
5617 unify_template_deduction_failure (bool explain_p, tree parm, tree arg)
5620 inform (input_location,
5621 " can't deduce a template for %qT from non-template type %qT",
5627 unify_template_argument_mismatch (bool explain_p, tree parm, tree arg)
5630 inform (input_location,
5631 " template argument %qE does not match %qD", arg, parm);
5636 unify_overload_resolution_failure (bool explain_p, tree arg)
5639 inform (input_location,
5640 " could not resolve address from overloaded function %qE",
5645 /* Attempt to convert the non-type template parameter EXPR to the
5646 indicated TYPE. If the conversion is successful, return the
5647 converted value. If the conversion is unsuccessful, return
5648 NULL_TREE if we issued an error message, or error_mark_node if we
5649 did not. We issue error messages for out-and-out bad template
5650 parameters, but not simply because the conversion failed, since we
5651 might be just trying to do argument deduction. Both TYPE and EXPR
5652 must be non-dependent.
5654 The conversion follows the special rules described in
5655 [temp.arg.nontype], and it is much more strict than an implicit
5658 This function is called twice for each template argument (see
5659 lookup_template_class for a more accurate description of this
5660 problem). This means that we need to handle expressions which
5661 are not valid in a C++ source, but can be created from the
5662 first call (for instance, casts to perform conversions). These
5663 hacks can go away after we fix the double coercion problem. */
5666 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5670 /* Detect immediately string literals as invalid non-type argument.
5671 This special-case is not needed for correctness (we would easily
5672 catch this later), but only to provide better diagnostic for this
5673 common user mistake. As suggested by DR 100, we do not mention
5674 linkage issues in the diagnostic as this is not the point. */
5675 /* FIXME we're making this OK. */
5676 if (TREE_CODE (expr) == STRING_CST)
5678 if (complain & tf_error)
5679 error ("%qE is not a valid template argument for type %qT "
5680 "because string literals can never be used in this context",
5685 /* Add the ADDR_EXPR now for the benefit of
5686 value_dependent_expression_p. */
5687 if (TYPE_PTROBV_P (type)
5688 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5689 expr = decay_conversion (expr);
5691 /* If we are in a template, EXPR may be non-dependent, but still
5692 have a syntactic, rather than semantic, form. For example, EXPR
5693 might be a SCOPE_REF, rather than the VAR_DECL to which the
5694 SCOPE_REF refers. Preserving the qualifying scope is necessary
5695 so that access checking can be performed when the template is
5696 instantiated -- but here we need the resolved form so that we can
5697 convert the argument. */
5698 if (TYPE_REF_OBJ_P (type)
5699 && has_value_dependent_address (expr))
5700 /* If we want the address and it's value-dependent, don't fold. */;
5701 else if (!type_unknown_p (expr))
5702 expr = fold_non_dependent_expr_sfinae (expr, complain);
5703 if (error_operand_p (expr))
5704 return error_mark_node;
5705 expr_type = TREE_TYPE (expr);
5706 if (TREE_CODE (type) == REFERENCE_TYPE)
5707 expr = mark_lvalue_use (expr);
5709 expr = mark_rvalue_use (expr);
5711 /* 14.3.2/5: The null pointer{,-to-member} conversion is applied
5712 to a non-type argument of "nullptr". */
5713 if (expr == nullptr_node
5714 && (TYPE_PTR_P (type) || TYPE_PTR_TO_MEMBER_P (type)))
5715 expr = convert (type, expr);
5717 /* In C++11, integral or enumeration non-type template arguments can be
5718 arbitrary constant expressions. Pointer and pointer to
5719 member arguments can be general constant expressions that evaluate
5720 to a null value, but otherwise still need to be of a specific form. */
5721 if (cxx_dialect >= cxx0x)
5723 if (TREE_CODE (expr) == PTRMEM_CST)
5724 /* A PTRMEM_CST is already constant, and a valid template
5725 argument for a parameter of pointer to member type, we just want
5726 to leave it in that form rather than lower it to a
5728 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5729 expr = maybe_constant_value (expr);
5730 else if (TYPE_PTR_P (type)
5731 || TYPE_PTR_TO_MEMBER_P (type))
5733 tree folded = maybe_constant_value (expr);
5734 if (TYPE_PTR_P (type) ? integer_zerop (folded)
5735 : null_member_pointer_value_p (folded))
5740 /* HACK: Due to double coercion, we can get a
5741 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5742 which is the tree that we built on the first call (see
5743 below when coercing to reference to object or to reference to
5744 function). We just strip everything and get to the arg.
5745 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5747 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5749 tree probe_type, probe = expr;
5750 if (REFERENCE_REF_P (probe))
5751 probe = TREE_OPERAND (probe, 0);
5752 probe_type = TREE_TYPE (probe);
5753 if (TREE_CODE (probe) == NOP_EXPR)
5755 /* ??? Maybe we could use convert_from_reference here, but we
5756 would need to relax its constraints because the NOP_EXPR
5757 could actually change the type to something more cv-qualified,
5758 and this is not folded by convert_from_reference. */
5759 tree addr = TREE_OPERAND (probe, 0);
5760 gcc_assert (TREE_CODE (probe_type) == REFERENCE_TYPE);
5761 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5762 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5763 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5764 (TREE_TYPE (probe_type),
5765 TREE_TYPE (TREE_TYPE (addr))));
5767 expr = TREE_OPERAND (addr, 0);
5768 expr_type = TREE_TYPE (expr);
5772 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5773 parameter is a pointer to object, through decay and
5774 qualification conversion. Let's strip everything. */
5775 else if (TREE_CODE (expr) == NOP_EXPR && TYPE_PTROBV_P (type))
5778 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5779 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5780 /* Skip the ADDR_EXPR only if it is part of the decay for
5781 an array. Otherwise, it is part of the original argument
5782 in the source code. */
5783 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5784 expr = TREE_OPERAND (expr, 0);
5785 expr_type = TREE_TYPE (expr);
5788 /* [temp.arg.nontype]/5, bullet 1
5790 For a non-type template-parameter of integral or enumeration type,
5791 integral promotions (_conv.prom_) and integral conversions
5792 (_conv.integral_) are applied. */
5793 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5795 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5796 t = maybe_constant_value (t);
5797 if (t != error_mark_node)
5800 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5801 return error_mark_node;
5803 /* Notice that there are constant expressions like '4 % 0' which
5804 do not fold into integer constants. */
5805 if (TREE_CODE (expr) != INTEGER_CST)
5807 if (complain & tf_error)
5809 int errs = errorcount, warns = warningcount;
5810 if (processing_template_decl
5811 && !require_potential_constant_expression (expr))
5813 expr = cxx_constant_value (expr);
5814 if (errorcount > errs || warningcount > warns)
5815 inform (EXPR_LOC_OR_HERE (expr),
5816 "in template argument for type %qT ", type);
5817 if (expr == error_mark_node)
5819 /* else cxx_constant_value complained but gave us
5820 a real constant, so go ahead. */
5821 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5827 /* [temp.arg.nontype]/5, bullet 2
5829 For a non-type template-parameter of type pointer to object,
5830 qualification conversions (_conv.qual_) and the array-to-pointer
5831 conversion (_conv.array_) are applied. */
5832 else if (TYPE_PTROBV_P (type))
5834 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5836 A template-argument for a non-type, non-template template-parameter
5837 shall be one of: [...]
5839 -- the name of a non-type template-parameter;
5840 -- the address of an object or function with external linkage, [...]
5841 expressed as "& id-expression" where the & is optional if the name
5842 refers to a function or array, or if the corresponding
5843 template-parameter is a reference.
5845 Here, we do not care about functions, as they are invalid anyway
5846 for a parameter of type pointer-to-object. */
5848 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5849 /* Non-type template parameters are OK. */
5851 else if (cxx_dialect >= cxx0x && integer_zerop (expr))
5852 /* Null pointer values are OK in C++11. */;
5853 else if (TREE_CODE (expr) != ADDR_EXPR
5854 && TREE_CODE (expr_type) != ARRAY_TYPE)
5856 if (TREE_CODE (expr) == VAR_DECL)
5858 error ("%qD is not a valid template argument "
5859 "because %qD is a variable, not the address of "
5864 /* Other values, like integer constants, might be valid
5865 non-type arguments of some other type. */
5866 return error_mark_node;
5872 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5873 ? TREE_OPERAND (expr, 0) : expr);
5874 if (TREE_CODE (decl) != VAR_DECL)
5876 error ("%qE is not a valid template argument of type %qT "
5877 "because %qE is not a variable",
5881 else if (cxx_dialect < cxx0x && !DECL_EXTERNAL_LINKAGE_P (decl))
5883 error ("%qE is not a valid template argument of type %qT "
5884 "because %qD does not have external linkage",
5888 else if (cxx_dialect >= cxx0x && decl_linkage (decl) == lk_none)
5890 error ("%qE is not a valid template argument of type %qT "
5891 "because %qD has no linkage",
5897 expr = decay_conversion (expr);
5898 if (expr == error_mark_node)
5899 return error_mark_node;
5901 expr = perform_qualification_conversions (type, expr);
5902 if (expr == error_mark_node)
5903 return error_mark_node;
5905 /* [temp.arg.nontype]/5, bullet 3
5907 For a non-type template-parameter of type reference to object, no
5908 conversions apply. The type referred to by the reference may be more
5909 cv-qualified than the (otherwise identical) type of the
5910 template-argument. The template-parameter is bound directly to the
5911 template-argument, which must be an lvalue. */
5912 else if (TYPE_REF_OBJ_P (type))
5914 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5916 return error_mark_node;
5918 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5920 error ("%qE is not a valid template argument for type %qT "
5921 "because of conflicts in cv-qualification", expr, type);
5925 if (!real_lvalue_p (expr))
5927 error ("%qE is not a valid template argument for type %qT "
5928 "because it is not an lvalue", expr, type);
5932 /* [temp.arg.nontype]/1
5934 A template-argument for a non-type, non-template template-parameter
5935 shall be one of: [...]
5937 -- the address of an object or function with external linkage. */
5938 if (TREE_CODE (expr) == INDIRECT_REF
5939 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5941 expr = TREE_OPERAND (expr, 0);
5944 error ("%q#D is not a valid template argument for type %qT "
5945 "because a reference variable does not have a constant "
5946 "address", expr, type);
5953 error ("%qE is not a valid template argument for type %qT "
5954 "because it is not an object with external linkage",
5959 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5961 error ("%qE is not a valid template argument for type %qT "
5962 "because object %qD has not external linkage",
5967 expr = build_nop (type, build_address (expr));
5969 /* [temp.arg.nontype]/5, bullet 4
5971 For a non-type template-parameter of type pointer to function, only
5972 the function-to-pointer conversion (_conv.func_) is applied. If the
5973 template-argument represents a set of overloaded functions (or a
5974 pointer to such), the matching function is selected from the set
5976 else if (TYPE_PTRFN_P (type))
5978 /* If the argument is a template-id, we might not have enough
5979 context information to decay the pointer. */
5980 if (!type_unknown_p (expr_type))
5982 expr = decay_conversion (expr);
5983 if (expr == error_mark_node)
5984 return error_mark_node;
5987 if (cxx_dialect >= cxx0x && integer_zerop (expr))
5988 /* Null pointer values are OK in C++11. */
5989 return perform_qualification_conversions (type, expr);
5991 expr = convert_nontype_argument_function (type, expr);
5992 if (!expr || expr == error_mark_node)
5995 if (TREE_CODE (expr) != ADDR_EXPR)
5997 error ("%qE is not a valid template argument for type %qT", expr, type);
5998 error ("it must be the address of a function with external linkage");
6002 /* [temp.arg.nontype]/5, bullet 5
6004 For a non-type template-parameter of type reference to function, no
6005 conversions apply. If the template-argument represents a set of
6006 overloaded functions, the matching function is selected from the set
6008 else if (TYPE_REFFN_P (type))
6010 if (TREE_CODE (expr) == ADDR_EXPR)
6012 error ("%qE is not a valid template argument for type %qT "
6013 "because it is a pointer", expr, type);
6014 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
6018 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
6019 if (!expr || expr == error_mark_node)
6022 expr = build_nop (type, build_address (expr));
6024 /* [temp.arg.nontype]/5, bullet 6
6026 For a non-type template-parameter of type pointer to member function,
6027 no conversions apply. If the template-argument represents a set of
6028 overloaded member functions, the matching member function is selected
6029 from the set (_over.over_). */
6030 else if (TYPE_PTRMEMFUNC_P (type))
6032 expr = instantiate_type (type, expr, tf_none);
6033 if (expr == error_mark_node)
6034 return error_mark_node;
6036 /* [temp.arg.nontype] bullet 1 says the pointer to member
6037 expression must be a pointer-to-member constant. */
6038 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6039 return error_mark_node;
6041 /* There is no way to disable standard conversions in
6042 resolve_address_of_overloaded_function (called by
6043 instantiate_type). It is possible that the call succeeded by
6044 converting &B::I to &D::I (where B is a base of D), so we need
6045 to reject this conversion here.
6047 Actually, even if there was a way to disable standard conversions,
6048 it would still be better to reject them here so that we can
6049 provide a superior diagnostic. */
6050 if (!same_type_p (TREE_TYPE (expr), type))
6052 error ("%qE is not a valid template argument for type %qT "
6053 "because it is of type %qT", expr, type,
6055 /* If we are just one standard conversion off, explain. */
6056 if (can_convert (type, TREE_TYPE (expr)))
6057 inform (input_location,
6058 "standard conversions are not allowed in this context");
6062 /* [temp.arg.nontype]/5, bullet 7
6064 For a non-type template-parameter of type pointer to data member,
6065 qualification conversions (_conv.qual_) are applied. */
6066 else if (TYPE_PTRMEM_P (type))
6068 /* [temp.arg.nontype] bullet 1 says the pointer to member
6069 expression must be a pointer-to-member constant. */
6070 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6071 return error_mark_node;
6073 expr = perform_qualification_conversions (type, expr);
6074 if (expr == error_mark_node)
6077 else if (NULLPTR_TYPE_P (type))
6079 if (expr != nullptr_node)
6081 error ("%qE is not a valid template argument for type %qT "
6082 "because it is of type %qT", expr, type, TREE_TYPE (expr));
6087 /* A template non-type parameter must be one of the above. */
6091 /* Sanity check: did we actually convert the argument to the
6093 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6094 (type, TREE_TYPE (expr)));
6098 /* Subroutine of coerce_template_template_parms, which returns 1 if
6099 PARM_PARM and ARG_PARM match using the rule for the template
6100 parameters of template template parameters. Both PARM and ARG are
6101 template parameters; the rest of the arguments are the same as for
6102 coerce_template_template_parms.
6105 coerce_template_template_parm (tree parm,
6107 tsubst_flags_t complain,
6111 if (arg == NULL_TREE || arg == error_mark_node
6112 || parm == NULL_TREE || parm == error_mark_node)
6115 if (TREE_CODE (arg) != TREE_CODE (parm))
6118 switch (TREE_CODE (parm))
6121 /* We encounter instantiations of templates like
6122 template <template <template <class> class> class TT>
6125 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6126 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6128 if (!coerce_template_template_parms
6129 (parmparm, argparm, complain, in_decl, outer_args))
6135 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
6136 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6137 /* Argument is a parameter pack but parameter is not. */
6142 /* The tsubst call is used to handle cases such as
6144 template <int> class C {};
6145 template <class T, template <T> class TT> class D {};
6148 i.e. the parameter list of TT depends on earlier parameters. */
6149 if (!uses_template_parms (TREE_TYPE (arg))
6151 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
6155 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
6156 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6157 /* Argument is a parameter pack but parameter is not. */
6170 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
6171 template template parameters. Both PARM_PARMS and ARG_PARMS are
6172 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
6175 Consider the example:
6176 template <class T> class A;
6177 template<template <class U> class TT> class B;
6179 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
6180 the parameters to A, and OUTER_ARGS contains A. */
6183 coerce_template_template_parms (tree parm_parms,
6185 tsubst_flags_t complain,
6189 int nparms, nargs, i;
6193 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
6194 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
6196 nparms = TREE_VEC_LENGTH (parm_parms);
6197 nargs = TREE_VEC_LENGTH (arg_parms);
6199 /* Determine whether we have a parameter pack at the end of the
6200 template template parameter's template parameter list. */
6201 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
6203 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
6205 if (parm == error_mark_node)
6208 switch (TREE_CODE (parm))
6212 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6217 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6227 && !(variadic_p && nargs >= nparms - 1))
6230 /* Check all of the template parameters except the parameter pack at
6231 the end (if any). */
6232 for (i = 0; i < nparms - variadic_p; ++i)
6234 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
6235 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6238 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6239 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6241 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6249 /* Check each of the template parameters in the template
6250 argument against the template parameter pack at the end of
6251 the template template parameter. */
6252 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
6255 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6257 for (; i < nargs; ++i)
6259 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6262 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6264 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6273 /* Verifies that the deduced template arguments (in TARGS) for the
6274 template template parameters (in TPARMS) represent valid bindings,
6275 by comparing the template parameter list of each template argument
6276 to the template parameter list of its corresponding template
6277 template parameter, in accordance with DR150. This
6278 routine can only be called after all template arguments have been
6279 deduced. It will return TRUE if all of the template template
6280 parameter bindings are okay, FALSE otherwise. */
6282 template_template_parm_bindings_ok_p (tree tparms, tree targs)
6284 int i, ntparms = TREE_VEC_LENGTH (tparms);
6287 /* We're dealing with template parms in this process. */
6288 ++processing_template_decl;
6290 targs = INNERMOST_TEMPLATE_ARGS (targs);
6292 for (i = 0; i < ntparms; ++i)
6294 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
6295 tree targ = TREE_VEC_ELT (targs, i);
6297 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
6299 tree packed_args = NULL_TREE;
6302 if (ARGUMENT_PACK_P (targ))
6304 /* Look inside the argument pack. */
6305 packed_args = ARGUMENT_PACK_ARGS (targ);
6306 len = TREE_VEC_LENGTH (packed_args);
6309 for (idx = 0; idx < len; ++idx)
6311 tree targ_parms = NULL_TREE;
6314 /* Extract the next argument from the argument
6316 targ = TREE_VEC_ELT (packed_args, idx);
6318 if (PACK_EXPANSION_P (targ))
6319 /* Look at the pattern of the pack expansion. */
6320 targ = PACK_EXPANSION_PATTERN (targ);
6322 /* Extract the template parameters from the template
6324 if (TREE_CODE (targ) == TEMPLATE_DECL)
6325 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
6326 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
6327 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
6329 /* Verify that we can coerce the template template
6330 parameters from the template argument to the template
6331 parameter. This requires an exact match. */
6333 && !coerce_template_template_parms
6334 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
6349 --processing_template_decl;
6353 /* Since type attributes aren't mangled, we need to strip them from
6354 template type arguments. */
6357 canonicalize_type_argument (tree arg, tsubst_flags_t complain)
6360 if (!arg || arg == error_mark_node || arg == TYPE_CANONICAL (arg))
6362 mv = TYPE_MAIN_VARIANT (arg);
6363 arg = strip_typedefs (arg);
6364 if (TYPE_ALIGN (arg) != TYPE_ALIGN (mv)
6365 || TYPE_ATTRIBUTES (arg) != TYPE_ATTRIBUTES (mv))
6367 if (complain & tf_warning)
6368 warning (0, "ignoring attributes on template argument %qT", arg);
6369 arg = build_aligned_type (arg, TYPE_ALIGN (mv));
6370 arg = cp_build_type_attribute_variant (arg, TYPE_ATTRIBUTES (mv));
6375 /* Convert the indicated template ARG as necessary to match the
6376 indicated template PARM. Returns the converted ARG, or
6377 error_mark_node if the conversion was unsuccessful. Error and
6378 warning messages are issued under control of COMPLAIN. This
6379 conversion is for the Ith parameter in the parameter list. ARGS is
6380 the full set of template arguments deduced so far. */
6383 convert_template_argument (tree parm,
6386 tsubst_flags_t complain,
6392 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
6394 if (TREE_CODE (arg) == TREE_LIST
6395 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
6397 /* The template argument was the name of some
6398 member function. That's usually
6399 invalid, but static members are OK. In any
6400 case, grab the underlying fields/functions
6401 and issue an error later if required. */
6402 orig_arg = TREE_VALUE (arg);
6403 TREE_TYPE (arg) = unknown_type_node;
6408 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
6409 requires_type = (TREE_CODE (parm) == TYPE_DECL
6410 || requires_tmpl_type);
6412 /* When determining whether an argument pack expansion is a template,
6413 look at the pattern. */
6414 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
6415 arg = PACK_EXPANSION_PATTERN (arg);
6417 /* Deal with an injected-class-name used as a template template arg. */
6418 if (requires_tmpl_type && CLASS_TYPE_P (arg))
6420 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
6421 if (TREE_CODE (t) == TEMPLATE_DECL)
6423 if (cxx_dialect >= cxx0x)
6424 /* OK under DR 1004. */;
6425 else if (complain & tf_warning_or_error)
6426 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
6427 " used as template template argument", TYPE_NAME (arg));
6428 else if (flag_pedantic_errors)
6436 ((TREE_CODE (arg) == TEMPLATE_DECL
6437 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
6438 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6439 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
6442 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6443 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
6444 arg = TYPE_STUB_DECL (arg);
6446 is_type = TYPE_P (arg) || is_tmpl_type;
6448 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
6449 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
6451 if (TREE_CODE (TREE_OPERAND (arg, 1)) == BIT_NOT_EXPR)
6453 if (complain & tf_error)
6454 error ("invalid use of destructor %qE as a type", orig_arg);
6455 return error_mark_node;
6458 permerror (input_location,
6459 "to refer to a type member of a template parameter, "
6460 "use %<typename %E%>", orig_arg);
6462 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
6463 TREE_OPERAND (arg, 1),
6465 complain & tf_error);
6469 if (is_type != requires_type)
6473 if (complain & tf_error)
6475 error ("type/value mismatch at argument %d in template "
6476 "parameter list for %qD",
6479 error (" expected a constant of type %qT, got %qT",
6481 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6482 else if (requires_tmpl_type)
6483 error (" expected a class template, got %qE", orig_arg);
6485 error (" expected a type, got %qE", orig_arg);
6488 return error_mark_node;
6490 if (is_tmpl_type ^ requires_tmpl_type)
6492 if (in_decl && (complain & tf_error))
6494 error ("type/value mismatch at argument %d in template "
6495 "parameter list for %qD",
6498 error (" expected a type, got %qT", DECL_NAME (arg));
6500 error (" expected a class template, got %qT", orig_arg);
6502 return error_mark_node;
6507 if (requires_tmpl_type)
6509 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6510 /* The number of argument required is not known yet.
6511 Just accept it for now. */
6512 val = TREE_TYPE (arg);
6515 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6518 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6520 if (coerce_template_template_parms (parmparm, argparm,
6526 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6528 if (val != error_mark_node)
6530 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6531 val = TREE_TYPE (val);
6532 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6533 val = make_pack_expansion (val);
6538 if (in_decl && (complain & tf_error))
6540 error ("type/value mismatch at argument %d in "
6541 "template parameter list for %qD",
6543 error (" expected a template of type %qD, got %qT",
6547 val = error_mark_node;
6553 /* We only form one instance of each template specialization.
6554 Therefore, if we use a non-canonical variant (i.e., a
6555 typedef), any future messages referring to the type will use
6556 the typedef, which is confusing if those future uses do not
6557 themselves also use the typedef. */
6559 val = canonicalize_type_argument (val, complain);
6563 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6565 if (invalid_nontype_parm_type_p (t, complain))
6566 return error_mark_node;
6568 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6570 if (same_type_p (t, TREE_TYPE (orig_arg)))
6574 /* Not sure if this is reachable, but it doesn't hurt
6576 error ("type mismatch in nontype parameter pack");
6577 val = error_mark_node;
6580 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6581 /* We used to call digest_init here. However, digest_init
6582 will report errors, which we don't want when complain
6583 is zero. More importantly, digest_init will try too
6584 hard to convert things: for example, `0' should not be
6585 converted to pointer type at this point according to
6586 the standard. Accepting this is not merely an
6587 extension, since deciding whether or not these
6588 conversions can occur is part of determining which
6589 function template to call, or whether a given explicit
6590 argument specification is valid. */
6591 val = convert_nontype_argument (t, orig_arg, complain);
6595 if (val == NULL_TREE)
6596 val = error_mark_node;
6597 else if (val == error_mark_node && (complain & tf_error))
6598 error ("could not convert template argument %qE to %qT", orig_arg, t);
6600 if (TREE_CODE (val) == SCOPE_REF)
6602 /* Strip typedefs from the SCOPE_REF. */
6603 tree type = canonicalize_type_argument (TREE_TYPE (val), complain);
6604 tree scope = canonicalize_type_argument (TREE_OPERAND (val, 0),
6606 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6607 QUALIFIED_NAME_IS_TEMPLATE (val));
6614 /* Coerces the remaining template arguments in INNER_ARGS (from
6615 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6616 Returns the coerced argument pack. PARM_IDX is the position of this
6617 parameter in the template parameter list. ARGS is the original
6618 template argument list. */
6620 coerce_template_parameter_pack (tree parms,
6628 tsubst_flags_t complain)
6630 tree parm = TREE_VEC_ELT (parms, parm_idx);
6631 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6634 tree packed_types = NULL_TREE;
6636 if (arg_idx > nargs)
6639 packed_args = make_tree_vec (nargs - arg_idx);
6641 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6642 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6644 /* When the template parameter is a non-type template
6645 parameter pack whose type uses parameter packs, we need
6646 to look at each of the template arguments
6647 separately. Build a vector of the types for these
6648 non-type template parameters in PACKED_TYPES. */
6650 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6651 packed_types = tsubst_pack_expansion (expansion, args,
6654 if (packed_types == error_mark_node)
6655 return error_mark_node;
6657 /* Check that we have the right number of arguments. */
6659 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6660 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6663 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6664 error ("wrong number of template arguments (%d, should be %d)",
6665 nargs, needed_parms);
6666 return error_mark_node;
6669 /* If we aren't able to check the actual arguments now
6670 (because they haven't been expanded yet), we can at least
6671 verify that all of the types used for the non-type
6672 template parameter pack are, in fact, valid for non-type
6673 template parameters. */
6675 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6677 int j, len = TREE_VEC_LENGTH (packed_types);
6678 for (j = 0; j < len; ++j)
6680 tree t = TREE_VEC_ELT (packed_types, j);
6681 if (invalid_nontype_parm_type_p (t, complain))
6682 return error_mark_node;
6687 /* Convert the remaining arguments, which will be a part of the
6688 parameter pack "parm". */
6689 for (; arg_idx < nargs; ++arg_idx)
6691 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6692 tree actual_parm = TREE_VALUE (parm);
6694 if (packed_types && !PACK_EXPANSION_P (arg))
6696 /* When we have a vector of types (corresponding to the
6697 non-type template parameter pack that uses parameter
6698 packs in its type, as mention above), and the
6699 argument is not an expansion (which expands to a
6700 currently unknown number of arguments), clone the
6701 parm and give it the next type in PACKED_TYPES. */
6702 actual_parm = copy_node (actual_parm);
6703 TREE_TYPE (actual_parm) =
6704 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6707 if (arg != error_mark_node)
6708 arg = convert_template_argument (actual_parm,
6709 arg, new_args, complain, parm_idx,
6711 if (arg == error_mark_node)
6713 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6716 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6717 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6718 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6721 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6722 TREE_TYPE (argument_pack)
6723 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6724 TREE_CONSTANT (argument_pack) = 1;
6727 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6728 #ifdef ENABLE_CHECKING
6729 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6730 TREE_VEC_LENGTH (packed_args));
6732 return argument_pack;
6735 /* Convert all template arguments to their appropriate types, and
6736 return a vector containing the innermost resulting template
6737 arguments. If any error occurs, return error_mark_node. Error and
6738 warning messages are issued under control of COMPLAIN.
6740 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6741 for arguments not specified in ARGS. Otherwise, if
6742 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6743 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6744 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6748 coerce_template_parms (tree parms,
6751 tsubst_flags_t complain,
6752 bool require_all_args,
6753 bool use_default_args)
6755 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6758 tree new_inner_args;
6759 int saved_unevaluated_operand;
6760 int saved_inhibit_evaluation_warnings;
6762 /* When used as a boolean value, indicates whether this is a
6763 variadic template parameter list. Since it's an int, we can also
6764 subtract it from nparms to get the number of non-variadic
6767 int post_variadic_parms = 0;
6769 if (args == error_mark_node)
6770 return error_mark_node;
6772 nparms = TREE_VEC_LENGTH (parms);
6774 /* Determine if there are any parameter packs. */
6775 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6777 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6779 ++post_variadic_parms;
6780 if (template_parameter_pack_p (tparm))
6784 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6785 /* If there are no parameters that follow a parameter pack, we need to
6786 expand any argument packs so that we can deduce a parameter pack from
6787 some non-packed args followed by an argument pack, as in variadic85.C.
6788 If there are such parameters, we need to leave argument packs intact
6789 so the arguments are assigned properly. This can happen when dealing
6790 with a nested class inside a partial specialization of a class
6791 template, as in variadic92.C, or when deducing a template parameter pack
6792 from a sub-declarator, as in variadic114.C. */
6793 if (!post_variadic_parms)
6794 inner_args = expand_template_argument_pack (inner_args);
6796 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6797 if ((nargs > nparms && !variadic_p)
6798 || (nargs < nparms - variadic_p
6800 && (!use_default_args
6801 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6802 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6804 if (complain & tf_error)
6808 nparms -= variadic_p;
6809 error ("wrong number of template arguments "
6810 "(%d, should be %d or more)", nargs, nparms);
6813 error ("wrong number of template arguments "
6814 "(%d, should be %d)", nargs, nparms);
6817 error ("provided for %q+D", in_decl);
6820 return error_mark_node;
6823 /* We need to evaluate the template arguments, even though this
6824 template-id may be nested within a "sizeof". */
6825 saved_unevaluated_operand = cp_unevaluated_operand;
6826 cp_unevaluated_operand = 0;
6827 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6828 c_inhibit_evaluation_warnings = 0;
6829 new_inner_args = make_tree_vec (nparms);
6830 new_args = add_outermost_template_args (args, new_inner_args);
6831 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6836 /* Get the Ith template parameter. */
6837 parm = TREE_VEC_ELT (parms, parm_idx);
6839 if (parm == error_mark_node)
6841 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6845 /* Calculate the next argument. */
6846 if (arg_idx < nargs)
6847 arg = TREE_VEC_ELT (inner_args, arg_idx);
6851 if (template_parameter_pack_p (TREE_VALUE (parm))
6852 && !(arg && ARGUMENT_PACK_P (arg)))
6854 /* All remaining arguments will be placed in the
6855 template parameter pack PARM. */
6856 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6857 inner_args, arg_idx,
6861 /* Store this argument. */
6862 if (arg == error_mark_node)
6864 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6866 /* We are done with all of the arguments. */
6873 if (PACK_EXPANSION_P (arg))
6875 /* We don't know how many args we have yet, just
6876 use the unconverted ones for now. */
6877 new_inner_args = args;
6881 else if (require_all_args)
6883 /* There must be a default arg in this case. */
6884 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6886 /* The position of the first default template argument,
6887 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6889 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6890 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6895 if (arg == error_mark_node)
6897 if (complain & tf_error)
6898 error ("template argument %d is invalid", arg_idx + 1);
6901 /* This only occurs if there was an error in the template
6902 parameter list itself (which we would already have
6903 reported) that we are trying to recover from, e.g., a class
6904 template with a parameter list such as
6905 template<typename..., typename>. */
6908 arg = convert_template_argument (TREE_VALUE (parm),
6909 arg, new_args, complain,
6912 if (arg == error_mark_node)
6914 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6916 cp_unevaluated_operand = saved_unevaluated_operand;
6917 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6920 return error_mark_node;
6922 #ifdef ENABLE_CHECKING
6923 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6924 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6925 TREE_VEC_LENGTH (new_inner_args));
6928 return new_inner_args;
6931 /* Returns 1 if template args OT and NT are equivalent. */
6934 template_args_equal (tree ot, tree nt)
6938 if (nt == NULL_TREE || ot == NULL_TREE)
6941 if (TREE_CODE (nt) == TREE_VEC)
6942 /* For member templates */
6943 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6944 else if (PACK_EXPANSION_P (ot))
6945 return (PACK_EXPANSION_P (nt)
6946 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6947 PACK_EXPANSION_PATTERN (nt))
6948 && template_args_equal (PACK_EXPANSION_EXTRA_ARGS (ot),
6949 PACK_EXPANSION_EXTRA_ARGS (nt)));
6950 else if (ARGUMENT_PACK_P (ot))
6955 if (!ARGUMENT_PACK_P (nt))
6958 opack = ARGUMENT_PACK_ARGS (ot);
6959 npack = ARGUMENT_PACK_ARGS (nt);
6960 len = TREE_VEC_LENGTH (opack);
6961 if (TREE_VEC_LENGTH (npack) != len)
6963 for (i = 0; i < len; ++i)
6964 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6965 TREE_VEC_ELT (npack, i)))
6969 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6971 /* We get here probably because we are in the middle of substituting
6972 into the pattern of a pack expansion. In that case the
6973 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6974 interested in. So we want to use the initial pack argument for
6976 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6977 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6978 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6979 return template_args_equal (ot, nt);
6981 else if (TYPE_P (nt))
6982 return TYPE_P (ot) && same_type_p (ot, nt);
6983 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6986 return cp_tree_equal (ot, nt);
6989 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of
6990 template arguments. Returns 0 otherwise, and updates OLDARG_PTR and
6991 NEWARG_PTR with the offending arguments if they are non-NULL. */
6994 comp_template_args_with_info (tree oldargs, tree newargs,
6995 tree *oldarg_ptr, tree *newarg_ptr)
6999 if (oldargs == newargs)
7002 if (!oldargs || !newargs)
7005 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
7008 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
7010 tree nt = TREE_VEC_ELT (newargs, i);
7011 tree ot = TREE_VEC_ELT (oldargs, i);
7013 if (! template_args_equal (ot, nt))
7015 if (oldarg_ptr != NULL)
7017 if (newarg_ptr != NULL)
7025 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
7026 of template arguments. Returns 0 otherwise. */
7029 comp_template_args (tree oldargs, tree newargs)
7031 return comp_template_args_with_info (oldargs, newargs, NULL, NULL);
7035 add_pending_template (tree d)
7037 tree ti = (TYPE_P (d)
7038 ? CLASSTYPE_TEMPLATE_INFO (d)
7039 : DECL_TEMPLATE_INFO (d));
7040 struct pending_template *pt;
7043 if (TI_PENDING_TEMPLATE_FLAG (ti))
7046 /* We are called both from instantiate_decl, where we've already had a
7047 tinst_level pushed, and instantiate_template, where we haven't.
7049 level = !current_tinst_level || current_tinst_level->decl != d;
7052 push_tinst_level (d);
7054 pt = ggc_alloc_pending_template ();
7056 pt->tinst = current_tinst_level;
7057 if (last_pending_template)
7058 last_pending_template->next = pt;
7060 pending_templates = pt;
7062 last_pending_template = pt;
7064 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
7071 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
7072 ARGLIST. Valid choices for FNS are given in the cp-tree.def
7073 documentation for TEMPLATE_ID_EXPR. */
7076 lookup_template_function (tree fns, tree arglist)
7080 if (fns == error_mark_node || arglist == error_mark_node)
7081 return error_mark_node;
7083 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
7085 if (!is_overloaded_fn (fns) && TREE_CODE (fns) != IDENTIFIER_NODE)
7087 error ("%q#D is not a function template", fns);
7088 return error_mark_node;
7091 if (BASELINK_P (fns))
7093 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
7095 BASELINK_FUNCTIONS (fns),
7100 type = TREE_TYPE (fns);
7101 if (TREE_CODE (fns) == OVERLOAD || !type)
7102 type = unknown_type_node;
7104 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
7107 /* Within the scope of a template class S<T>, the name S gets bound
7108 (in build_self_reference) to a TYPE_DECL for the class, not a
7109 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
7110 or one of its enclosing classes, and that type is a template,
7111 return the associated TEMPLATE_DECL. Otherwise, the original
7114 Also handle the case when DECL is a TREE_LIST of ambiguous
7115 injected-class-names from different bases. */
7118 maybe_get_template_decl_from_type_decl (tree decl)
7120 if (decl == NULL_TREE)
7123 /* DR 176: A lookup that finds an injected-class-name (10.2
7124 [class.member.lookup]) can result in an ambiguity in certain cases
7125 (for example, if it is found in more than one base class). If all of
7126 the injected-class-names that are found refer to specializations of
7127 the same class template, and if the name is followed by a
7128 template-argument-list, the reference refers to the class template
7129 itself and not a specialization thereof, and is not ambiguous. */
7130 if (TREE_CODE (decl) == TREE_LIST)
7132 tree t, tmpl = NULL_TREE;
7133 for (t = decl; t; t = TREE_CHAIN (t))
7135 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
7138 else if (tmpl != elt)
7141 if (tmpl && t == NULL_TREE)
7147 return (decl != NULL_TREE
7148 && DECL_SELF_REFERENCE_P (decl)
7149 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
7150 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
7153 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
7154 parameters, find the desired type.
7156 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
7158 IN_DECL, if non-NULL, is the template declaration we are trying to
7161 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
7162 the class we are looking up.
7164 Issue error and warning messages under control of COMPLAIN.
7166 If the template class is really a local class in a template
7167 function, then the FUNCTION_CONTEXT is the function in which it is
7170 ??? Note that this function is currently called *twice* for each
7171 template-id: the first time from the parser, while creating the
7172 incomplete type (finish_template_type), and the second type during the
7173 real instantiation (instantiate_template_class). This is surely something
7174 that we want to avoid. It also causes some problems with argument
7175 coercion (see convert_nontype_argument for more information on this). */
7178 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
7179 int entering_scope, tsubst_flags_t complain)
7181 tree templ = NULL_TREE, parmlist;
7188 if (TREE_CODE (d1) == IDENTIFIER_NODE)
7190 tree value = innermost_non_namespace_value (d1);
7191 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
7196 push_decl_namespace (context);
7197 templ = lookup_name (d1);
7198 templ = maybe_get_template_decl_from_type_decl (templ);
7200 pop_decl_namespace ();
7203 context = DECL_CONTEXT (templ);
7205 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
7207 tree type = TREE_TYPE (d1);
7209 /* If we are declaring a constructor, say A<T>::A<T>, we will get
7210 an implicit typename for the second A. Deal with it. */
7211 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
7212 type = TREE_TYPE (type);
7214 if (CLASSTYPE_TEMPLATE_INFO (type))
7216 templ = CLASSTYPE_TI_TEMPLATE (type);
7217 d1 = DECL_NAME (templ);
7220 else if (TREE_CODE (d1) == ENUMERAL_TYPE
7221 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
7223 templ = TYPE_TI_TEMPLATE (d1);
7224 d1 = DECL_NAME (templ);
7226 else if (TREE_CODE (d1) == TEMPLATE_DECL
7227 && DECL_TEMPLATE_RESULT (d1)
7228 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
7231 d1 = DECL_NAME (templ);
7232 context = DECL_CONTEXT (templ);
7235 /* Issue an error message if we didn't find a template. */
7238 if (complain & tf_error)
7239 error ("%qT is not a template", d1);
7240 return error_mark_node;
7243 if (TREE_CODE (templ) != TEMPLATE_DECL
7244 /* Make sure it's a user visible template, if it was named by
7246 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
7247 && !PRIMARY_TEMPLATE_P (templ)))
7249 if (complain & tf_error)
7251 error ("non-template type %qT used as a template", d1);
7253 error ("for template declaration %q+D", in_decl);
7255 return error_mark_node;
7258 complain &= ~tf_user;
7260 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
7262 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
7263 template arguments */
7269 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
7271 /* Consider an example where a template template parameter declared as
7273 template <class T, class U = std::allocator<T> > class TT
7275 The template parameter level of T and U are one level larger than
7276 of TT. To proper process the default argument of U, say when an
7277 instantiation `TT<int>' is seen, we need to build the full
7278 arguments containing {int} as the innermost level. Outer levels,
7279 available when not appearing as default template argument, can be
7280 obtained from the arguments of the enclosing template.
7282 Suppose that TT is later substituted with std::vector. The above
7283 instantiation is `TT<int, std::allocator<T> >' with TT at
7284 level 1, and T at level 2, while the template arguments at level 1
7285 becomes {std::vector} and the inner level 2 is {int}. */
7287 outer = DECL_CONTEXT (templ);
7289 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
7290 else if (current_template_parms)
7291 /* This is an argument of the current template, so we haven't set
7292 DECL_CONTEXT yet. */
7293 outer = current_template_args ();
7296 arglist = add_to_template_args (outer, arglist);
7298 arglist2 = coerce_template_parms (parmlist, arglist, templ,
7300 /*require_all_args=*/true,
7301 /*use_default_args=*/true);
7302 if (arglist2 == error_mark_node
7303 || (!uses_template_parms (arglist2)
7304 && check_instantiated_args (templ, arglist2, complain)))
7305 return error_mark_node;
7307 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
7312 tree template_type = TREE_TYPE (templ);
7315 tree found = NULL_TREE;
7318 int is_dependent_type;
7319 int use_partial_inst_tmpl = false;
7321 if (template_type == error_mark_node)
7322 /* An error occured while building the template TEMPL, and a
7323 diagnostic has most certainly been emitted for that
7324 already. Let's propagate that error. */
7325 return error_mark_node;
7327 gen_tmpl = most_general_template (templ);
7328 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
7329 parm_depth = TMPL_PARMS_DEPTH (parmlist);
7330 arg_depth = TMPL_ARGS_DEPTH (arglist);
7332 if (arg_depth == 1 && parm_depth > 1)
7334 /* We've been given an incomplete set of template arguments.
7337 template <class T> struct S1 {
7338 template <class U> struct S2 {};
7339 template <class U> struct S2<U*> {};
7342 we will be called with an ARGLIST of `U*', but the
7343 TEMPLATE will be `template <class T> template
7344 <class U> struct S1<T>::S2'. We must fill in the missing
7347 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
7349 arg_depth = TMPL_ARGS_DEPTH (arglist);
7352 /* Now we should have enough arguments. */
7353 gcc_assert (parm_depth == arg_depth);
7355 /* From here on, we're only interested in the most general
7358 /* Calculate the BOUND_ARGS. These will be the args that are
7359 actually tsubst'd into the definition to create the
7363 /* We have multiple levels of arguments to coerce, at once. */
7365 int saved_depth = TMPL_ARGS_DEPTH (arglist);
7367 tree bound_args = make_tree_vec (parm_depth);
7369 for (i = saved_depth,
7370 t = DECL_TEMPLATE_PARMS (gen_tmpl);
7371 i > 0 && t != NULL_TREE;
7372 --i, t = TREE_CHAIN (t))
7375 if (i == saved_depth)
7376 a = coerce_template_parms (TREE_VALUE (t),
7379 /*require_all_args=*/true,
7380 /*use_default_args=*/true);
7382 /* Outer levels should have already been coerced. */
7383 a = TMPL_ARGS_LEVEL (arglist, i);
7385 /* Don't process further if one of the levels fails. */
7386 if (a == error_mark_node)
7388 /* Restore the ARGLIST to its full size. */
7389 TREE_VEC_LENGTH (arglist) = saved_depth;
7390 return error_mark_node;
7393 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
7395 /* We temporarily reduce the length of the ARGLIST so
7396 that coerce_template_parms will see only the arguments
7397 corresponding to the template parameters it is
7399 TREE_VEC_LENGTH (arglist)--;
7402 /* Restore the ARGLIST to its full size. */
7403 TREE_VEC_LENGTH (arglist) = saved_depth;
7405 arglist = bound_args;
7409 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
7410 INNERMOST_TEMPLATE_ARGS (arglist),
7413 /*require_all_args=*/true,
7414 /*use_default_args=*/true);
7416 if (arglist == error_mark_node)
7417 /* We were unable to bind the arguments. */
7418 return error_mark_node;
7420 /* In the scope of a template class, explicit references to the
7421 template class refer to the type of the template, not any
7422 instantiation of it. For example, in:
7424 template <class T> class C { void f(C<T>); }
7426 the `C<T>' is just the same as `C'. Outside of the
7427 class, however, such a reference is an instantiation. */
7429 || !PRIMARY_TEMPLATE_P (gen_tmpl)
7430 || currently_open_class (template_type))
7431 /* comp_template_args is expensive, check it last. */
7432 && comp_template_args (TYPE_TI_ARGS (template_type),
7434 return template_type;
7436 /* If we already have this specialization, return it. */
7437 elt.tmpl = gen_tmpl;
7439 hash = hash_specialization (&elt);
7440 entry = (spec_entry *) htab_find_with_hash (type_specializations,
7446 is_dependent_type = uses_template_parms (arglist);
7448 /* If the deduced arguments are invalid, then the binding
7450 if (!is_dependent_type
7451 && check_instantiated_args (gen_tmpl,
7452 INNERMOST_TEMPLATE_ARGS (arglist),
7454 return error_mark_node;
7456 if (!is_dependent_type
7457 && !PRIMARY_TEMPLATE_P (gen_tmpl)
7458 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
7459 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
7461 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
7462 DECL_NAME (gen_tmpl),
7463 /*tag_scope=*/ts_global);
7467 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
7469 if (context == error_mark_node)
7470 return error_mark_node;
7473 context = global_namespace;
7475 /* Create the type. */
7476 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
7478 if (!is_dependent_type)
7480 set_current_access_from_decl (TYPE_NAME (template_type));
7481 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
7482 tsubst (ENUM_UNDERLYING_TYPE (template_type),
7483 arglist, complain, in_decl),
7484 SCOPED_ENUM_P (template_type), NULL);
7488 /* We don't want to call start_enum for this type, since
7489 the values for the enumeration constants may involve
7490 template parameters. And, no one should be interested
7491 in the enumeration constants for such a type. */
7492 t = cxx_make_type (ENUMERAL_TYPE);
7493 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7495 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7496 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7497 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7499 else if (DECL_ALIAS_TEMPLATE_P (gen_tmpl))
7501 /* The user referred to a specialization of an alias
7502 template represented by GEN_TMPL.
7504 [temp.alias]/2 says:
7506 When a template-id refers to the specialization of an
7507 alias template, it is equivalent to the associated
7508 type obtained by substitution of its
7509 template-arguments for the template-parameters in the
7510 type-id of the alias template. */
7512 t = tsubst (TREE_TYPE (gen_tmpl), arglist, complain, in_decl);
7513 /* Note that the call above (by indirectly calling
7514 register_specialization in tsubst_decl) registers the
7515 TYPE_DECL representing the specialization of the alias
7516 template. So next time someone substitutes ARGLIST for
7517 the template parms into the alias template (GEN_TMPL),
7518 she'll get that TYPE_DECL back. */
7520 if (t == error_mark_node)
7523 else if (CLASS_TYPE_P (template_type))
7525 t = make_class_type (TREE_CODE (template_type));
7526 CLASSTYPE_DECLARED_CLASS (t)
7527 = CLASSTYPE_DECLARED_CLASS (template_type);
7528 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7529 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7531 /* A local class. Make sure the decl gets registered properly. */
7532 if (context == current_function_decl)
7533 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7535 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7536 /* This instantiation is another name for the primary
7537 template type. Set the TYPE_CANONICAL field
7539 TYPE_CANONICAL (t) = template_type;
7540 else if (any_template_arguments_need_structural_equality_p (arglist))
7541 /* Some of the template arguments require structural
7542 equality testing, so this template class requires
7543 structural equality testing. */
7544 SET_TYPE_STRUCTURAL_EQUALITY (t);
7549 /* If we called start_enum or pushtag above, this information
7550 will already be set up. */
7553 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7555 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7556 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7557 DECL_SOURCE_LOCATION (type_decl)
7558 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7561 type_decl = TYPE_NAME (t);
7563 if (CLASS_TYPE_P (template_type))
7565 TREE_PRIVATE (type_decl)
7566 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7567 TREE_PROTECTED (type_decl)
7568 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7569 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7571 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7572 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7576 /* Let's consider the explicit specialization of a member
7577 of a class template specialization that is implicitely instantiated,
7582 template<class U> struct M {}; //#0
7587 struct S<int>::M<char> //#1
7591 [temp.expl.spec]/4 says this is valid.
7593 In this case, when we write:
7596 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7599 When we encounter #1, we want to store the partial instantiation
7600 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7602 For all cases other than this "explicit specialization of member of a
7603 class template", we just want to store the most general template into
7604 the CLASSTYPE_TI_TEMPLATE of M.
7606 This case of "explicit specialization of member of a class template"
7608 1/ the enclosing class is an instantiation of, and therefore not
7609 the same as, the context of the most general template, and
7610 2/ we aren't looking at the partial instantiation itself, i.e.
7611 the innermost arguments are not the same as the innermost parms of
7612 the most general template.
7614 So it's only when 1/ and 2/ happens that we want to use the partial
7615 instantiation of the member template in lieu of its most general
7618 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7619 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7620 /* the enclosing class must be an instantiation... */
7621 && CLASS_TYPE_P (context)
7622 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7624 tree partial_inst_args;
7625 TREE_VEC_LENGTH (arglist)--;
7626 ++processing_template_decl;
7628 tsubst (INNERMOST_TEMPLATE_ARGS
7629 (TYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7630 arglist, complain, NULL_TREE);
7631 --processing_template_decl;
7632 TREE_VEC_LENGTH (arglist)++;
7633 use_partial_inst_tmpl =
7634 /*...and we must not be looking at the partial instantiation
7636 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7640 if (!use_partial_inst_tmpl)
7641 /* This case is easy; there are no member templates involved. */
7645 /* This is a full instantiation of a member template. Find
7646 the partial instantiation of which this is an instance. */
7648 /* Temporarily reduce by one the number of levels in the ARGLIST
7649 so as to avoid comparing the last set of arguments. */
7650 TREE_VEC_LENGTH (arglist)--;
7651 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7652 TREE_VEC_LENGTH (arglist)++;
7653 /* FOUND is either a proper class type, or an alias
7654 template specialization. In the later case, it's a
7655 TYPE_DECL, resulting from the substituting of arguments
7656 for parameters in the TYPE_DECL of the alias template
7657 done earlier. So be careful while getting the template
7659 found = TREE_CODE (found) == TYPE_DECL
7660 ? TYPE_TI_TEMPLATE (TREE_TYPE (found))
7661 : CLASSTYPE_TI_TEMPLATE (found);
7664 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7667 slot = htab_find_slot_with_hash (type_specializations,
7668 &elt, hash, INSERT);
7669 entry = ggc_alloc_spec_entry ();
7673 /* Note this use of the partial instantiation so we can check it
7674 later in maybe_process_partial_specialization. */
7675 DECL_TEMPLATE_INSTANTIATIONS (templ)
7676 = tree_cons (arglist, t,
7677 DECL_TEMPLATE_INSTANTIATIONS (templ));
7679 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7680 /* Now that the type has been registered on the instantiations
7681 list, we set up the enumerators. Because the enumeration
7682 constants may involve the enumeration type itself, we make
7683 sure to register the type first, and then create the
7684 constants. That way, doing tsubst_expr for the enumeration
7685 constants won't result in recursive calls here; we'll find
7686 the instantiation and exit above. */
7687 tsubst_enum (template_type, t, arglist);
7689 if (CLASS_TYPE_P (template_type) && is_dependent_type)
7690 /* If the type makes use of template parameters, the
7691 code that generates debugging information will crash. */
7692 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7694 /* Possibly limit visibility based on template args. */
7695 TREE_PUBLIC (type_decl) = 1;
7696 determine_visibility (type_decl);
7702 /* Wrapper for lookup_template_class_1. */
7705 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7706 int entering_scope, tsubst_flags_t complain)
7709 timevar_push (TV_TEMPLATE_INST);
7710 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7711 entering_scope, complain);
7712 timevar_pop (TV_TEMPLATE_INST);
7720 /* True when we should also visit template parameters that occur in
7721 non-deduced contexts. */
7722 bool include_nondeduced_p;
7723 struct pointer_set_t *visited;
7726 /* Called from for_each_template_parm via walk_tree. */
7729 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7732 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7733 tree_fn_t fn = pfd->fn;
7734 void *data = pfd->data;
7737 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7738 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7739 pfd->include_nondeduced_p))
7740 return error_mark_node;
7742 switch (TREE_CODE (t))
7745 if (TYPE_PTRMEMFUNC_P (t))
7751 if (!TYPE_TEMPLATE_INFO (t))
7753 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7754 fn, data, pfd->visited,
7755 pfd->include_nondeduced_p))
7756 return error_mark_node;
7760 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7761 fn, data, pfd->visited,
7762 pfd->include_nondeduced_p)
7763 || for_each_template_parm (TYPE_MAX_VALUE (t),
7764 fn, data, pfd->visited,
7765 pfd->include_nondeduced_p))
7766 return error_mark_node;
7770 /* Since we're not going to walk subtrees, we have to do this
7772 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7773 pfd->visited, pfd->include_nondeduced_p))
7774 return error_mark_node;
7778 /* Check the return type. */
7779 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7780 pfd->include_nondeduced_p))
7781 return error_mark_node;
7783 /* Check the parameter types. Since default arguments are not
7784 instantiated until they are needed, the TYPE_ARG_TYPES may
7785 contain expressions that involve template parameters. But,
7786 no-one should be looking at them yet. And, once they're
7787 instantiated, they don't contain template parameters, so
7788 there's no point in looking at them then, either. */
7792 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7793 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7794 pfd->visited, pfd->include_nondeduced_p))
7795 return error_mark_node;
7797 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7798 want walk_tree walking into them itself. */
7804 case UNDERLYING_TYPE:
7805 if (pfd->include_nondeduced_p
7806 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7808 pfd->include_nondeduced_p))
7809 return error_mark_node;
7814 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7815 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7816 pfd->visited, pfd->include_nondeduced_p))
7817 return error_mark_node;
7822 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7823 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7824 pfd->visited, pfd->include_nondeduced_p))
7825 return error_mark_node;
7826 if (DECL_CONTEXT (t)
7827 && pfd->include_nondeduced_p
7828 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7829 pfd->visited, pfd->include_nondeduced_p))
7830 return error_mark_node;
7833 case BOUND_TEMPLATE_TEMPLATE_PARM:
7834 /* Record template parameters such as `T' inside `TT<T>'. */
7835 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7836 pfd->include_nondeduced_p))
7837 return error_mark_node;
7840 case TEMPLATE_TEMPLATE_PARM:
7841 case TEMPLATE_TYPE_PARM:
7842 case TEMPLATE_PARM_INDEX:
7843 if (fn && (*fn)(t, data))
7844 return error_mark_node;
7846 return error_mark_node;
7850 /* A template template parameter is encountered. */
7851 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7852 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7853 pfd->include_nondeduced_p))
7854 return error_mark_node;
7856 /* Already substituted template template parameter */
7862 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7864 pfd->include_nondeduced_p))
7865 return error_mark_node;
7869 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7870 && pfd->include_nondeduced_p
7871 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7872 (TREE_TYPE (t)), fn, data,
7873 pfd->visited, pfd->include_nondeduced_p))
7874 return error_mark_node;
7879 /* If there's no type, then this thing must be some expression
7880 involving template parameters. */
7881 if (!fn && !TREE_TYPE (t))
7882 return error_mark_node;
7887 case IMPLICIT_CONV_EXPR:
7888 case REINTERPRET_CAST_EXPR:
7889 case CONST_CAST_EXPR:
7890 case STATIC_CAST_EXPR:
7891 case DYNAMIC_CAST_EXPR:
7895 case PSEUDO_DTOR_EXPR:
7897 return error_mark_node;
7904 /* We didn't find any template parameters we liked. */
7908 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7909 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7910 call FN with the parameter and the DATA.
7911 If FN returns nonzero, the iteration is terminated, and
7912 for_each_template_parm returns 1. Otherwise, the iteration
7913 continues. If FN never returns a nonzero value, the value
7914 returned by for_each_template_parm is 0. If FN is NULL, it is
7915 considered to be the function which always returns 1.
7917 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7918 parameters that occur in non-deduced contexts. When false, only
7919 visits those template parameters that can be deduced. */
7922 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7923 struct pointer_set_t *visited,
7924 bool include_nondeduced_p)
7926 struct pair_fn_data pfd;
7932 pfd.include_nondeduced_p = include_nondeduced_p;
7934 /* Walk the tree. (Conceptually, we would like to walk without
7935 duplicates, but for_each_template_parm_r recursively calls
7936 for_each_template_parm, so we would need to reorganize a fair
7937 bit to use walk_tree_without_duplicates, so we keep our own
7940 pfd.visited = visited;
7942 pfd.visited = pointer_set_create ();
7943 result = cp_walk_tree (&t,
7944 for_each_template_parm_r,
7946 pfd.visited) != NULL_TREE;
7951 pointer_set_destroy (pfd.visited);
7958 /* Returns true if T depends on any template parameter. */
7961 uses_template_parms (tree t)
7964 int saved_processing_template_decl;
7966 saved_processing_template_decl = processing_template_decl;
7967 if (!saved_processing_template_decl)
7968 processing_template_decl = 1;
7970 dependent_p = dependent_type_p (t);
7971 else if (TREE_CODE (t) == TREE_VEC)
7972 dependent_p = any_dependent_template_arguments_p (t);
7973 else if (TREE_CODE (t) == TREE_LIST)
7974 dependent_p = (uses_template_parms (TREE_VALUE (t))
7975 || uses_template_parms (TREE_CHAIN (t)));
7976 else if (TREE_CODE (t) == TYPE_DECL)
7977 dependent_p = dependent_type_p (TREE_TYPE (t));
7980 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7981 || TREE_CODE (t) == OVERLOAD
7983 || TREE_CODE (t) == IDENTIFIER_NODE
7984 || TREE_CODE (t) == TRAIT_EXPR
7985 || TREE_CODE (t) == CONSTRUCTOR
7986 || CONSTANT_CLASS_P (t))
7987 dependent_p = (type_dependent_expression_p (t)
7988 || value_dependent_expression_p (t));
7991 gcc_assert (t == error_mark_node);
7992 dependent_p = false;
7995 processing_template_decl = saved_processing_template_decl;
8000 /* Returns true if T depends on any template parameter with level LEVEL. */
8003 uses_template_parms_level (tree t, int level)
8005 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
8006 /*include_nondeduced_p=*/true);
8009 /* Returns TRUE iff INST is an instantiation we don't need to do in an
8010 ill-formed translation unit, i.e. a variable or function that isn't
8011 usable in a constant expression. */
8014 neglectable_inst_p (tree d)
8017 && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d)
8018 : decl_maybe_constant_var_p (d)));
8021 /* Returns TRUE iff we should refuse to instantiate DECL because it's
8022 neglectable and instantiated from within an erroneous instantiation. */
8025 limit_bad_template_recursion (tree decl)
8027 struct tinst_level *lev = current_tinst_level;
8028 int errs = errorcount + sorrycount;
8029 if (lev == NULL || errs == 0 || !neglectable_inst_p (decl))
8032 for (; lev; lev = lev->next)
8033 if (neglectable_inst_p (lev->decl))
8036 return (lev && errs > lev->errors);
8039 static int tinst_depth;
8040 extern int max_tinst_depth;
8041 #ifdef GATHER_STATISTICS
8044 static GTY(()) struct tinst_level *last_error_tinst_level;
8046 /* We're starting to instantiate D; record the template instantiation context
8047 for diagnostics and to restore it later. */
8050 push_tinst_level (tree d)
8052 struct tinst_level *new_level;
8054 if (tinst_depth >= max_tinst_depth)
8056 last_error_tinst_level = current_tinst_level;
8057 if (TREE_CODE (d) == TREE_LIST)
8058 error ("template instantiation depth exceeds maximum of %d (use "
8059 "-ftemplate-depth= to increase the maximum) substituting %qS",
8060 max_tinst_depth, d);
8062 error ("template instantiation depth exceeds maximum of %d (use "
8063 "-ftemplate-depth= to increase the maximum) instantiating %qD",
8064 max_tinst_depth, d);
8066 print_instantiation_context ();
8071 /* If the current instantiation caused problems, don't let it instantiate
8072 anything else. Do allow deduction substitution and decls usable in
8073 constant expressions. */
8074 if (limit_bad_template_recursion (d))
8077 new_level = ggc_alloc_tinst_level ();
8078 new_level->decl = d;
8079 new_level->locus = input_location;
8080 new_level->errors = errorcount+sorrycount;
8081 new_level->in_system_header_p = in_system_header;
8082 new_level->next = current_tinst_level;
8083 current_tinst_level = new_level;
8086 #ifdef GATHER_STATISTICS
8087 if (tinst_depth > depth_reached)
8088 depth_reached = tinst_depth;
8094 /* We're done instantiating this template; return to the instantiation
8098 pop_tinst_level (void)
8100 /* Restore the filename and line number stashed away when we started
8101 this instantiation. */
8102 input_location = current_tinst_level->locus;
8103 current_tinst_level = current_tinst_level->next;
8107 /* We're instantiating a deferred template; restore the template
8108 instantiation context in which the instantiation was requested, which
8109 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
8112 reopen_tinst_level (struct tinst_level *level)
8114 struct tinst_level *t;
8117 for (t = level; t; t = t->next)
8120 current_tinst_level = level;
8122 if (current_tinst_level)
8123 current_tinst_level->errors = errorcount+sorrycount;
8127 /* Returns the TINST_LEVEL which gives the original instantiation
8130 struct tinst_level *
8131 outermost_tinst_level (void)
8133 struct tinst_level *level = current_tinst_level;
8136 level = level->next;
8140 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
8143 parameter_of_template_p (tree parm, tree templ)
8148 if (!parm || !templ)
8151 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
8152 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8154 parms = DECL_TEMPLATE_PARMS (templ);
8155 parms = INNERMOST_TEMPLATE_PARMS (parms);
8157 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
8159 tree p = TREE_VALUE (TREE_VEC_ELT (parms, i));
8161 || (DECL_INITIAL (parm)
8162 && DECL_INITIAL (parm) == DECL_INITIAL (p)))
8169 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
8170 vector of template arguments, as for tsubst.
8172 Returns an appropriate tsubst'd friend declaration. */
8175 tsubst_friend_function (tree decl, tree args)
8179 if (TREE_CODE (decl) == FUNCTION_DECL
8180 && DECL_TEMPLATE_INSTANTIATION (decl)
8181 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
8182 /* This was a friend declared with an explicit template
8183 argument list, e.g.:
8187 to indicate that f was a template instantiation, not a new
8188 function declaration. Now, we have to figure out what
8189 instantiation of what template. */
8191 tree template_id, arglist, fns;
8194 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
8196 /* Friend functions are looked up in the containing namespace scope.
8197 We must enter that scope, to avoid finding member functions of the
8198 current class with same name. */
8199 push_nested_namespace (ns);
8200 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
8201 tf_warning_or_error, NULL_TREE,
8202 /*integral_constant_expression_p=*/false);
8203 pop_nested_namespace (ns);
8204 arglist = tsubst (DECL_TI_ARGS (decl), args,
8205 tf_warning_or_error, NULL_TREE);
8206 template_id = lookup_template_function (fns, arglist);
8208 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8209 tmpl = determine_specialization (template_id, new_friend,
8211 /*need_member_template=*/0,
8212 TREE_VEC_LENGTH (args),
8214 return instantiate_template (tmpl, new_args, tf_error);
8217 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8219 /* The NEW_FRIEND will look like an instantiation, to the
8220 compiler, but is not an instantiation from the point of view of
8221 the language. For example, we might have had:
8223 template <class T> struct S {
8224 template <class U> friend void f(T, U);
8227 Then, in S<int>, template <class U> void f(int, U) is not an
8228 instantiation of anything. */
8229 if (new_friend == error_mark_node)
8230 return error_mark_node;
8232 DECL_USE_TEMPLATE (new_friend) = 0;
8233 if (TREE_CODE (decl) == TEMPLATE_DECL)
8235 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
8236 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
8237 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
8240 /* The mangled name for the NEW_FRIEND is incorrect. The function
8241 is not a template instantiation and should not be mangled like
8242 one. Therefore, we forget the mangling here; we'll recompute it
8243 later if we need it. */
8244 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
8246 SET_DECL_RTL (new_friend, NULL);
8247 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
8250 if (DECL_NAMESPACE_SCOPE_P (new_friend))
8253 tree new_friend_template_info;
8254 tree new_friend_result_template_info;
8256 int new_friend_is_defn;
8258 /* We must save some information from NEW_FRIEND before calling
8259 duplicate decls since that function will free NEW_FRIEND if
8261 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
8262 new_friend_is_defn =
8263 (DECL_INITIAL (DECL_TEMPLATE_RESULT
8264 (template_for_substitution (new_friend)))
8266 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
8268 /* This declaration is a `primary' template. */
8269 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
8271 new_friend_result_template_info
8272 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
8275 new_friend_result_template_info = NULL_TREE;
8277 /* Make the init_value nonzero so pushdecl knows this is a defn. */
8278 if (new_friend_is_defn)
8279 DECL_INITIAL (new_friend) = error_mark_node;
8281 /* Inside pushdecl_namespace_level, we will push into the
8282 current namespace. However, the friend function should go
8283 into the namespace of the template. */
8284 ns = decl_namespace_context (new_friend);
8285 push_nested_namespace (ns);
8286 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
8287 pop_nested_namespace (ns);
8289 if (old_decl == error_mark_node)
8290 return error_mark_node;
8292 if (old_decl != new_friend)
8294 /* This new friend declaration matched an existing
8295 declaration. For example, given:
8297 template <class T> void f(T);
8298 template <class U> class C {
8299 template <class T> friend void f(T) {}
8302 the friend declaration actually provides the definition
8303 of `f', once C has been instantiated for some type. So,
8304 old_decl will be the out-of-class template declaration,
8305 while new_friend is the in-class definition.
8307 But, if `f' was called before this point, the
8308 instantiation of `f' will have DECL_TI_ARGS corresponding
8309 to `T' but not to `U', references to which might appear
8310 in the definition of `f'. Previously, the most general
8311 template for an instantiation of `f' was the out-of-class
8312 version; now it is the in-class version. Therefore, we
8313 run through all specialization of `f', adding to their
8314 DECL_TI_ARGS appropriately. In particular, they need a
8315 new set of outer arguments, corresponding to the
8316 arguments for this class instantiation.
8318 The same situation can arise with something like this:
8321 template <class T> class C {
8325 when `C<int>' is instantiated. Now, `f(int)' is defined
8328 if (!new_friend_is_defn)
8329 /* On the other hand, if the in-class declaration does
8330 *not* provide a definition, then we don't want to alter
8331 existing definitions. We can just leave everything
8336 tree new_template = TI_TEMPLATE (new_friend_template_info);
8337 tree new_args = TI_ARGS (new_friend_template_info);
8339 /* Overwrite whatever template info was there before, if
8340 any, with the new template information pertaining to
8342 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
8344 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
8346 /* We should have called reregister_specialization in
8348 gcc_assert (retrieve_specialization (new_template,
8352 /* Instantiate it if the global has already been used. */
8353 if (DECL_ODR_USED (old_decl))
8354 instantiate_decl (old_decl, /*defer_ok=*/true,
8355 /*expl_inst_class_mem_p=*/false);
8361 /* Indicate that the old function template is a partial
8363 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
8364 = new_friend_result_template_info;
8366 gcc_assert (new_template
8367 == most_general_template (new_template));
8368 gcc_assert (new_template != old_decl);
8370 /* Reassign any specializations already in the hash table
8371 to the new more general template, and add the
8372 additional template args. */
8373 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
8377 tree spec = TREE_VALUE (t);
8380 elt.tmpl = old_decl;
8381 elt.args = DECL_TI_ARGS (spec);
8382 elt.spec = NULL_TREE;
8384 htab_remove_elt (decl_specializations, &elt);
8387 = add_outermost_template_args (new_args,
8388 DECL_TI_ARGS (spec));
8390 register_specialization
8391 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
8394 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
8398 /* The information from NEW_FRIEND has been merged into OLD_DECL
8399 by duplicate_decls. */
8400 new_friend = old_decl;
8405 tree context = DECL_CONTEXT (new_friend);
8409 template <class T> class C {
8410 template <class U> friend void C1<U>::f (); // case 1
8411 friend void C2<T>::f (); // case 2
8413 we only need to make sure CONTEXT is a complete type for
8414 case 2. To distinguish between the two cases, we note that
8415 CONTEXT of case 1 remains dependent type after tsubst while
8416 this isn't true for case 2. */
8417 ++processing_template_decl;
8418 dependent_p = dependent_type_p (context);
8419 --processing_template_decl;
8422 && !complete_type_or_else (context, NULL_TREE))
8423 return error_mark_node;
8425 if (COMPLETE_TYPE_P (context))
8427 /* Check to see that the declaration is really present, and,
8428 possibly obtain an improved declaration. */
8429 tree fn = check_classfn (context,
8430 new_friend, NULL_TREE);
8440 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
8441 template arguments, as for tsubst.
8443 Returns an appropriate tsubst'd friend type or error_mark_node on
8447 tsubst_friend_class (tree friend_tmpl, tree args)
8453 context = CP_DECL_CONTEXT (friend_tmpl);
8455 if (context != global_namespace)
8457 if (TREE_CODE (context) == NAMESPACE_DECL)
8458 push_nested_namespace (context);
8460 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
8463 /* Look for a class template declaration. We look for hidden names
8464 because two friend declarations of the same template are the
8465 same. For example, in:
8468 template <typename> friend class F;
8470 template <typename> struct B {
8471 template <typename> friend class F;
8474 both F templates are the same. */
8475 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
8476 /*block_p=*/true, 0,
8477 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
8479 /* But, if we don't find one, it might be because we're in a
8480 situation like this:
8488 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
8489 for `S<int>', not the TEMPLATE_DECL. */
8490 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
8492 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
8493 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
8496 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
8498 /* The friend template has already been declared. Just
8499 check to see that the declarations match, and install any new
8500 default parameters. We must tsubst the default parameters,
8501 of course. We only need the innermost template parameters
8502 because that is all that redeclare_class_template will look
8504 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
8505 > TMPL_ARGS_DEPTH (args))
8508 location_t saved_input_location;
8509 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
8510 args, tf_warning_or_error);
8512 saved_input_location = input_location;
8513 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
8514 redeclare_class_template (TREE_TYPE (tmpl), parms);
8515 input_location = saved_input_location;
8519 friend_type = TREE_TYPE (tmpl);
8523 /* The friend template has not already been declared. In this
8524 case, the instantiation of the template class will cause the
8525 injection of this template into the global scope. */
8526 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
8527 if (tmpl == error_mark_node)
8528 return error_mark_node;
8530 /* The new TMPL is not an instantiation of anything, so we
8531 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
8532 the new type because that is supposed to be the corresponding
8533 template decl, i.e., TMPL. */
8534 DECL_USE_TEMPLATE (tmpl) = 0;
8535 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
8536 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
8537 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
8538 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
8540 /* Inject this template into the global scope. */
8541 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
8544 if (context != global_namespace)
8546 if (TREE_CODE (context) == NAMESPACE_DECL)
8547 pop_nested_namespace (context);
8549 pop_nested_class ();
8555 /* Returns zero if TYPE cannot be completed later due to circularity.
8556 Otherwise returns one. */
8559 can_complete_type_without_circularity (tree type)
8561 if (type == NULL_TREE || type == error_mark_node)
8563 else if (COMPLETE_TYPE_P (type))
8565 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
8566 return can_complete_type_without_circularity (TREE_TYPE (type));
8567 else if (CLASS_TYPE_P (type)
8568 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
8574 /* Apply any attributes which had to be deferred until instantiation
8575 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8576 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8579 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8580 tree args, tsubst_flags_t complain, tree in_decl)
8582 tree last_dep = NULL_TREE;
8586 for (t = attributes; t; t = TREE_CHAIN (t))
8587 if (ATTR_IS_DEPENDENT (t))
8590 attributes = copy_list (attributes);
8594 if (DECL_P (*decl_p))
8596 if (TREE_TYPE (*decl_p) == error_mark_node)
8598 p = &DECL_ATTRIBUTES (*decl_p);
8601 p = &TYPE_ATTRIBUTES (*decl_p);
8605 tree late_attrs = NULL_TREE;
8606 tree *q = &late_attrs;
8608 for (*p = attributes; *p; )
8611 if (ATTR_IS_DEPENDENT (t))
8613 *p = TREE_CHAIN (t);
8614 TREE_CHAIN (t) = NULL_TREE;
8615 /* If the first attribute argument is an identifier, don't
8616 pass it through tsubst. Attributes like mode, format,
8617 cleanup and several target specific attributes expect it
8620 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8621 && TREE_VALUE (TREE_VALUE (t))
8622 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8623 == IDENTIFIER_NODE))
8626 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8628 /*integral_constant_expression_p=*/false);
8629 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8631 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8636 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8637 /*integral_constant_expression_p=*/false);
8639 q = &TREE_CHAIN (t);
8642 p = &TREE_CHAIN (t);
8645 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8649 /* Perform (or defer) access check for typedefs that were referenced
8650 from within the template TMPL code.
8651 This is a subroutine of instantiate_template and instantiate_class_template.
8652 TMPL is the template to consider and TARGS is the list of arguments of
8656 perform_typedefs_access_check (tree tmpl, tree targs)
8658 location_t saved_location;
8660 qualified_typedef_usage_t *iter;
8663 || (!CLASS_TYPE_P (tmpl)
8664 && TREE_CODE (tmpl) != FUNCTION_DECL))
8667 saved_location = input_location;
8668 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8669 get_types_needing_access_check (tmpl),
8672 tree type_decl = iter->typedef_decl;
8673 tree type_scope = iter->context;
8675 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8678 if (uses_template_parms (type_decl))
8679 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8680 if (uses_template_parms (type_scope))
8681 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8683 /* Make access check error messages point to the location
8684 of the use of the typedef. */
8685 input_location = iter->locus;
8686 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8687 type_decl, type_decl);
8689 input_location = saved_location;
8693 instantiate_class_template_1 (tree type)
8695 tree templ, args, pattern, t, member;
8699 unsigned int saved_maximum_field_alignment;
8701 if (type == error_mark_node)
8702 return error_mark_node;
8704 if (COMPLETE_OR_OPEN_TYPE_P (type)
8705 || uses_template_parms (type))
8708 /* Figure out which template is being instantiated. */
8709 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8710 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8712 /* Determine what specialization of the original template to
8714 t = most_specialized_class (type, templ, tf_warning_or_error);
8715 if (t == error_mark_node)
8717 TYPE_BEING_DEFINED (type) = 1;
8718 return error_mark_node;
8722 /* This TYPE is actually an instantiation of a partial
8723 specialization. We replace the innermost set of ARGS with
8724 the arguments appropriate for substitution. For example,
8727 template <class T> struct S {};
8728 template <class T> struct S<T*> {};
8730 and supposing that we are instantiating S<int*>, ARGS will
8731 presently be {int*} -- but we need {int}. */
8732 pattern = TREE_TYPE (t);
8733 args = TREE_PURPOSE (t);
8737 pattern = TREE_TYPE (templ);
8738 args = CLASSTYPE_TI_ARGS (type);
8741 /* If the template we're instantiating is incomplete, then clearly
8742 there's nothing we can do. */
8743 if (!COMPLETE_TYPE_P (pattern))
8746 /* If we've recursively instantiated too many templates, stop. */
8747 if (! push_tinst_level (type))
8750 /* Now we're really doing the instantiation. Mark the type as in
8751 the process of being defined. */
8752 TYPE_BEING_DEFINED (type) = 1;
8754 /* We may be in the middle of deferred access check. Disable
8756 push_deferring_access_checks (dk_no_deferred);
8758 push_to_top_level ();
8759 /* Use #pragma pack from the template context. */
8760 saved_maximum_field_alignment = maximum_field_alignment;
8761 maximum_field_alignment = TYPE_PRECISION (pattern);
8763 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8765 /* Set the input location to the most specialized template definition.
8766 This is needed if tsubsting causes an error. */
8767 typedecl = TYPE_MAIN_DECL (pattern);
8768 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8769 DECL_SOURCE_LOCATION (typedecl);
8771 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8772 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8773 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8774 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8775 if (ANON_AGGR_TYPE_P (pattern))
8776 SET_ANON_AGGR_TYPE_P (type);
8777 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8779 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8780 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8781 /* Adjust visibility for template arguments. */
8782 determine_visibility (TYPE_MAIN_DECL (type));
8784 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8786 pbinfo = TYPE_BINFO (pattern);
8788 /* We should never instantiate a nested class before its enclosing
8789 class; we need to look up the nested class by name before we can
8790 instantiate it, and that lookup should instantiate the enclosing
8792 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8793 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8795 base_list = NULL_TREE;
8796 if (BINFO_N_BASE_BINFOS (pbinfo))
8802 /* We must enter the scope containing the type, as that is where
8803 the accessibility of types named in dependent bases are
8805 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8807 /* Substitute into each of the bases to determine the actual
8809 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8812 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8813 tree expanded_bases = NULL_TREE;
8816 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8819 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8820 args, tf_error, NULL_TREE);
8821 if (expanded_bases == error_mark_node)
8824 len = TREE_VEC_LENGTH (expanded_bases);
8827 for (idx = 0; idx < len; idx++)
8830 /* Extract the already-expanded base class. */
8831 base = TREE_VEC_ELT (expanded_bases, idx);
8833 /* Substitute to figure out the base class. */
8834 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8837 if (base == error_mark_node)
8840 base_list = tree_cons (access, base, base_list);
8841 if (BINFO_VIRTUAL_P (pbase_binfo))
8842 TREE_TYPE (base_list) = integer_type_node;
8846 /* The list is now in reverse order; correct that. */
8847 base_list = nreverse (base_list);
8850 pop_scope (pushed_scope);
8852 /* Now call xref_basetypes to set up all the base-class
8854 xref_basetypes (type, base_list);
8856 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8857 (int) ATTR_FLAG_TYPE_IN_PLACE,
8858 args, tf_error, NULL_TREE);
8859 fixup_attribute_variants (type);
8861 /* Now that our base classes are set up, enter the scope of the
8862 class, so that name lookups into base classes, etc. will work
8863 correctly. This is precisely analogous to what we do in
8864 begin_class_definition when defining an ordinary non-template
8865 class, except we also need to push the enclosing classes. */
8866 push_nested_class (type);
8868 /* Now members are processed in the order of declaration. */
8869 for (member = CLASSTYPE_DECL_LIST (pattern);
8870 member; member = TREE_CHAIN (member))
8872 tree t = TREE_VALUE (member);
8874 if (TREE_PURPOSE (member))
8878 /* Build new CLASSTYPE_NESTED_UTDS. */
8881 bool class_template_p;
8883 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8884 && TYPE_LANG_SPECIFIC (t)
8885 && CLASSTYPE_IS_TEMPLATE (t));
8886 /* If the member is a class template, then -- even after
8887 substitution -- there may be dependent types in the
8888 template argument list for the class. We increment
8889 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8890 that function will assume that no types are dependent
8891 when outside of a template. */
8892 if (class_template_p)
8893 ++processing_template_decl;
8894 newtag = tsubst (t, args, tf_error, NULL_TREE);
8895 if (class_template_p)
8896 --processing_template_decl;
8897 if (newtag == error_mark_node)
8900 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8902 tree name = TYPE_IDENTIFIER (t);
8904 if (class_template_p)
8905 /* Unfortunately, lookup_template_class sets
8906 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8907 instantiation (i.e., for the type of a member
8908 template class nested within a template class.)
8909 This behavior is required for
8910 maybe_process_partial_specialization to work
8911 correctly, but is not accurate in this case;
8912 the TAG is not an instantiation of anything.
8913 (The corresponding TEMPLATE_DECL is an
8914 instantiation, but the TYPE is not.) */
8915 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8917 /* Now, we call pushtag to put this NEWTAG into the scope of
8918 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8919 pushtag calling push_template_decl. We don't have to do
8920 this for enums because it will already have been done in
8923 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8924 pushtag (name, newtag, /*tag_scope=*/ts_current);
8927 else if (TREE_CODE (t) == FUNCTION_DECL
8928 || DECL_FUNCTION_TEMPLATE_P (t))
8930 /* Build new TYPE_METHODS. */
8933 if (TREE_CODE (t) == TEMPLATE_DECL)
8934 ++processing_template_decl;
8935 r = tsubst (t, args, tf_error, NULL_TREE);
8936 if (TREE_CODE (t) == TEMPLATE_DECL)
8937 --processing_template_decl;
8938 set_current_access_from_decl (r);
8939 finish_member_declaration (r);
8940 /* Instantiate members marked with attribute used. */
8941 if (r != error_mark_node && DECL_PRESERVE_P (r))
8946 /* Build new TYPE_FIELDS. */
8947 if (TREE_CODE (t) == STATIC_ASSERT)
8950 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8951 tf_warning_or_error, NULL_TREE,
8952 /*integral_constant_expression_p=*/true);
8953 finish_static_assert (condition,
8954 STATIC_ASSERT_MESSAGE (t),
8955 STATIC_ASSERT_SOURCE_LOCATION (t),
8958 else if (TREE_CODE (t) != CONST_DECL)
8962 /* The file and line for this declaration, to
8963 assist in error message reporting. Since we
8964 called push_tinst_level above, we don't need to
8966 input_location = DECL_SOURCE_LOCATION (t);
8968 if (TREE_CODE (t) == TEMPLATE_DECL)
8969 ++processing_template_decl;
8970 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8971 if (TREE_CODE (t) == TEMPLATE_DECL)
8972 --processing_template_decl;
8973 if (TREE_CODE (r) == VAR_DECL)
8977 [t]he initialization (and any associated
8978 side-effects) of a static data member does
8979 not occur unless the static data member is
8980 itself used in a way that requires the
8981 definition of the static data member to
8984 Therefore, we do not substitute into the
8985 initialized for the static data member here. */
8986 finish_static_data_member_decl
8989 /*init_const_expr_p=*/false,
8990 /*asmspec_tree=*/NULL_TREE,
8992 /* Instantiate members marked with attribute used. */
8993 if (r != error_mark_node && DECL_PRESERVE_P (r))
8996 else if (TREE_CODE (r) == FIELD_DECL)
8998 /* Determine whether R has a valid type and can be
8999 completed later. If R is invalid, then it is
9000 replaced by error_mark_node so that it will not be
9001 added to TYPE_FIELDS. */
9002 tree rtype = TREE_TYPE (r);
9003 if (can_complete_type_without_circularity (rtype))
9004 complete_type (rtype);
9006 if (!COMPLETE_TYPE_P (rtype))
9008 cxx_incomplete_type_error (r, rtype);
9009 r = error_mark_node;
9013 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
9014 such a thing will already have been added to the field
9015 list by tsubst_enum in finish_member_declaration in the
9016 CLASSTYPE_NESTED_UTDS case above. */
9017 if (!(TREE_CODE (r) == TYPE_DECL
9018 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
9019 && DECL_ARTIFICIAL (r)))
9021 set_current_access_from_decl (r);
9022 finish_member_declaration (r);
9029 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
9031 /* Build new CLASSTYPE_FRIEND_CLASSES. */
9033 tree friend_type = t;
9034 bool adjust_processing_template_decl = false;
9036 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9038 /* template <class T> friend class C; */
9039 friend_type = tsubst_friend_class (friend_type, args);
9040 adjust_processing_template_decl = true;
9042 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
9044 /* template <class T> friend class C::D; */
9045 friend_type = tsubst (friend_type, args,
9046 tf_warning_or_error, NULL_TREE);
9047 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9048 friend_type = TREE_TYPE (friend_type);
9049 adjust_processing_template_decl = true;
9051 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
9052 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
9054 /* This could be either
9058 when dependent_type_p is false or
9060 template <class U> friend class T::C;
9063 friend_type = tsubst (friend_type, args,
9064 tf_warning_or_error, NULL_TREE);
9065 /* Bump processing_template_decl for correct
9066 dependent_type_p calculation. */
9067 ++processing_template_decl;
9068 if (dependent_type_p (friend_type))
9069 adjust_processing_template_decl = true;
9070 --processing_template_decl;
9072 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
9073 && hidden_name_p (TYPE_NAME (friend_type)))
9077 where C hasn't been declared yet. Let's lookup name
9078 from namespace scope directly, bypassing any name that
9079 come from dependent base class. */
9080 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
9082 /* The call to xref_tag_from_type does injection for friend
9084 push_nested_namespace (ns);
9086 xref_tag_from_type (friend_type, NULL_TREE,
9087 /*tag_scope=*/ts_current);
9088 pop_nested_namespace (ns);
9090 else if (uses_template_parms (friend_type))
9091 /* friend class C<T>; */
9092 friend_type = tsubst (friend_type, args,
9093 tf_warning_or_error, NULL_TREE);
9098 where C is already declared or
9100 friend class C<int>;
9102 We don't have to do anything in these cases. */
9104 if (adjust_processing_template_decl)
9105 /* Trick make_friend_class into realizing that the friend
9106 we're adding is a template, not an ordinary class. It's
9107 important that we use make_friend_class since it will
9108 perform some error-checking and output cross-reference
9110 ++processing_template_decl;
9112 if (friend_type != error_mark_node)
9113 make_friend_class (type, friend_type, /*complain=*/false);
9115 if (adjust_processing_template_decl)
9116 --processing_template_decl;
9120 /* Build new DECL_FRIENDLIST. */
9123 /* The file and line for this declaration, to
9124 assist in error message reporting. Since we
9125 called push_tinst_level above, we don't need to
9127 input_location = DECL_SOURCE_LOCATION (t);
9129 if (TREE_CODE (t) == TEMPLATE_DECL)
9131 ++processing_template_decl;
9132 push_deferring_access_checks (dk_no_check);
9135 r = tsubst_friend_function (t, args);
9136 add_friend (type, r, /*complain=*/false);
9137 if (TREE_CODE (t) == TEMPLATE_DECL)
9139 pop_deferring_access_checks ();
9140 --processing_template_decl;
9146 if (CLASSTYPE_LAMBDA_EXPR (type))
9148 tree decl = lambda_function (type);
9151 tree lambda = CLASSTYPE_LAMBDA_EXPR (type);
9152 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
9154 apply_lambda_return_type (lambda, void_type_node);
9155 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE;
9157 instantiate_decl (decl, false, false);
9158 maybe_add_lambda_conv_op (type);
9161 gcc_assert (errorcount);
9164 /* Set the file and line number information to whatever is given for
9165 the class itself. This puts error messages involving generated
9166 implicit functions at a predictable point, and the same point
9167 that would be used for non-template classes. */
9168 input_location = DECL_SOURCE_LOCATION (typedecl);
9170 unreverse_member_declarations (type);
9171 finish_struct_1 (type);
9172 TYPE_BEING_DEFINED (type) = 0;
9174 /* We don't instantiate default arguments for member functions. 14.7.1:
9176 The implicit instantiation of a class template specialization causes
9177 the implicit instantiation of the declarations, but not of the
9178 definitions or default arguments, of the class member functions,
9179 member classes, static data members and member templates.... */
9181 /* Some typedefs referenced from within the template code need to be access
9182 checked at template instantiation time, i.e now. These types were
9183 added to the template at parsing time. Let's get those and perform
9184 the access checks then. */
9185 perform_typedefs_access_check (pattern, args);
9186 perform_deferred_access_checks ();
9187 pop_nested_class ();
9188 maximum_field_alignment = saved_maximum_field_alignment;
9189 pop_from_top_level ();
9190 pop_deferring_access_checks ();
9193 /* The vtable for a template class can be emitted in any translation
9194 unit in which the class is instantiated. When there is no key
9195 method, however, finish_struct_1 will already have added TYPE to
9196 the keyed_classes list. */
9197 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
9198 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
9203 /* Wrapper for instantiate_class_template_1. */
9206 instantiate_class_template (tree type)
9209 timevar_push (TV_TEMPLATE_INST);
9210 ret = instantiate_class_template_1 (type);
9211 timevar_pop (TV_TEMPLATE_INST);
9216 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9222 else if (TYPE_P (t))
9223 r = tsubst (t, args, complain, in_decl);
9226 if (!(complain & tf_warning))
9227 ++c_inhibit_evaluation_warnings;
9228 r = tsubst_expr (t, args, complain, in_decl,
9229 /*integral_constant_expression_p=*/true);
9230 if (!(complain & tf_warning))
9231 --c_inhibit_evaluation_warnings;
9232 /* Preserve the raw-reference nature of T. */
9233 if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE
9234 && REFERENCE_REF_P (r))
9235 r = TREE_OPERAND (r, 0);
9240 /* Given a function parameter pack TMPL_PARM and some function parameters
9241 instantiated from it at *SPEC_P, return a NONTYPE_ARGUMENT_PACK of them
9242 and set *SPEC_P to point at the next point in the list. */
9245 extract_fnparm_pack (tree tmpl_parm, tree *spec_p)
9247 /* Collect all of the extra "packed" parameters into an
9251 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
9252 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
9253 tree spec_parm = *spec_p;
9256 for (len = 0; spec_parm; ++len, spec_parm = TREE_CHAIN (spec_parm))
9258 && !function_parameter_expanded_from_pack_p (spec_parm, tmpl_parm))
9261 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
9262 parmvec = make_tree_vec (len);
9263 parmtypevec = make_tree_vec (len);
9264 spec_parm = *spec_p;
9265 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
9267 TREE_VEC_ELT (parmvec, i) = spec_parm;
9268 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
9271 /* Build the argument packs. */
9272 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
9273 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
9274 TREE_TYPE (argpack) = argtypepack;
9275 *spec_p = spec_parm;
9280 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
9281 NONTYPE_ARGUMENT_PACK. */
9284 make_fnparm_pack (tree spec_parm)
9286 return extract_fnparm_pack (NULL_TREE, &spec_parm);
9289 /* Substitute ARGS into T, which is an pack expansion
9290 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
9291 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
9292 (if only a partial substitution could be performed) or
9293 ERROR_MARK_NODE if there was an error. */
9295 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
9299 tree pack, packs = NULL_TREE;
9300 bool unsubstituted_packs = false;
9301 bool real_packs = false;
9302 int missing_level = 0;
9305 htab_t saved_local_specializations = NULL;
9306 bool need_local_specializations = false;
9309 gcc_assert (PACK_EXPANSION_P (t));
9310 pattern = PACK_EXPANSION_PATTERN (t);
9312 /* Add in any args remembered from an earlier partial instantiation. */
9313 args = add_to_template_args (PACK_EXPANSION_EXTRA_ARGS (t), args);
9315 levels = TMPL_ARGS_DEPTH (args);
9317 /* Determine the argument packs that will instantiate the parameter
9318 packs used in the expansion expression. While we're at it,
9319 compute the number of arguments to be expanded and make sure it
9321 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
9322 pack = TREE_CHAIN (pack))
9324 tree parm_pack = TREE_VALUE (pack);
9325 tree arg_pack = NULL_TREE;
9326 tree orig_arg = NULL_TREE;
9329 if (TREE_CODE (parm_pack) == BASES)
9331 if (BASES_DIRECT (parm_pack))
9332 return calculate_direct_bases (tsubst_expr (BASES_TYPE (parm_pack),
9333 args, complain, in_decl, false));
9335 return calculate_bases (tsubst_expr (BASES_TYPE (parm_pack),
9336 args, complain, in_decl, false));
9338 if (TREE_CODE (parm_pack) == PARM_DECL)
9340 if (at_function_scope_p ())
9341 arg_pack = retrieve_local_specialization (parm_pack);
9344 /* We can't rely on local_specializations for a parameter
9345 name used later in a function declaration (such as in a
9346 late-specified return type). Even if it exists, it might
9347 have the wrong value for a recursive call. Just make a
9348 dummy decl, since it's only used for its type. */
9349 arg_pack = tsubst_decl (parm_pack, args, complain);
9350 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
9351 /* Partial instantiation of the parm_pack, we can't build
9352 up an argument pack yet. */
9353 arg_pack = NULL_TREE;
9355 arg_pack = make_fnparm_pack (arg_pack);
9356 need_local_specializations = true;
9362 template_parm_level_and_index (parm_pack, &level, &idx);
9364 if (level <= levels)
9365 arg_pack = TMPL_ARG (args, level, idx);
9368 orig_arg = arg_pack;
9369 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
9370 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
9372 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
9373 /* This can only happen if we forget to expand an argument
9374 pack somewhere else. Just return an error, silently. */
9376 result = make_tree_vec (1);
9377 TREE_VEC_ELT (result, 0) = error_mark_node;
9381 if (arg_from_parm_pack_p (arg_pack, parm_pack))
9382 /* The argument pack that the parameter maps to is just an
9383 expansion of the parameter itself, such as one would find
9384 in the implicit typedef of a class inside the class itself.
9385 Consider this parameter "unsubstituted", so that we will
9386 maintain the outer pack expansion. */
9387 arg_pack = NULL_TREE;
9392 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
9394 /* Don't bother trying to do a partial substitution with
9395 incomplete packs; we'll try again after deduction. */
9396 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
9401 else if (len != my_len)
9403 if (!(complain & tf_error))
9404 /* Fail quietly. */;
9405 else if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
9406 error ("mismatched argument pack lengths while expanding "
9410 error ("mismatched argument pack lengths while expanding "
9413 return error_mark_node;
9416 if (TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
9417 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack),
9419 /* This isn't a real argument pack yet. */;
9423 /* Keep track of the parameter packs and their corresponding
9425 packs = tree_cons (parm_pack, arg_pack, packs);
9426 TREE_TYPE (packs) = orig_arg;
9430 /* We can't substitute for this parameter pack. We use a flag as
9431 well as the missing_level counter because function parameter
9432 packs don't have a level. */
9433 unsubstituted_packs = true;
9434 if (!missing_level || missing_level > level)
9435 missing_level = level;
9439 /* We cannot expand this expansion expression, because we don't have
9440 all of the argument packs we need. */
9441 if (unsubstituted_packs)
9445 /* We got some full packs, but we can't substitute them in until we
9446 have values for all the packs. So remember these until then. */
9449 t = make_pack_expansion (pattern);
9451 /* The call to add_to_template_args above assumes no overlap
9452 between saved args and new args, so prune away any fake
9453 args, i.e. those that satisfied arg_from_parm_pack_p above. */
9454 if (missing_level && levels >= missing_level)
9456 gcc_assert (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args)
9457 && missing_level > 1);
9458 TREE_VEC_LENGTH (args) = missing_level - 1;
9459 save_args = copy_node (args);
9460 TREE_VEC_LENGTH (args) = levels;
9465 PACK_EXPANSION_EXTRA_ARGS (t) = save_args;
9469 /* There were no real arguments, we're just replacing a parameter
9470 pack with another version of itself. Substitute into the
9471 pattern and return a PACK_EXPANSION_*. The caller will need to
9473 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9474 t = tsubst_expr (pattern, args, complain, in_decl,
9475 /*integral_constant_expression_p=*/false);
9477 t = tsubst (pattern, args, complain, in_decl);
9478 t = make_pack_expansion (t);
9483 /* We could not find any argument packs that work. */
9485 return error_mark_node;
9487 if (need_local_specializations)
9489 /* We're in a late-specified return type, so create our own local
9490 specializations table; the current table is either NULL or (in the
9491 case of recursive unification) might have bindings that we don't
9492 want to use or alter. */
9493 saved_local_specializations = local_specializations;
9494 local_specializations = htab_create (37,
9495 hash_local_specialization,
9496 eq_local_specializations,
9500 /* For each argument in each argument pack, substitute into the
9502 result = make_tree_vec (len);
9503 for (i = 0; i < len; ++i)
9505 /* For parameter pack, change the substitution of the parameter
9506 pack to the ith argument in its argument pack, then expand
9508 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9510 tree parm = TREE_PURPOSE (pack);
9513 /* Select the Ith argument from the pack. */
9514 if (TREE_CODE (parm) == PARM_DECL)
9518 arg = make_node (ARGUMENT_PACK_SELECT);
9519 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9521 register_local_specialization (arg, parm);
9524 arg = retrieve_local_specialization (parm);
9529 template_parm_level_and_index (parm, &level, &idx);
9533 arg = make_node (ARGUMENT_PACK_SELECT);
9534 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9535 /* Update the corresponding argument. */
9536 TMPL_ARG (args, level, idx) = arg;
9539 /* Re-use the ARGUMENT_PACK_SELECT. */
9540 arg = TMPL_ARG (args, level, idx);
9542 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
9545 /* Substitute into the PATTERN with the altered arguments. */
9546 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9547 TREE_VEC_ELT (result, i) =
9548 tsubst_expr (pattern, args, complain, in_decl,
9549 /*integral_constant_expression_p=*/false);
9551 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
9553 if (TREE_VEC_ELT (result, i) == error_mark_node)
9555 result = error_mark_node;
9560 /* Update ARGS to restore the substitution from parameter packs to
9561 their argument packs. */
9562 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9564 tree parm = TREE_PURPOSE (pack);
9566 if (TREE_CODE (parm) == PARM_DECL)
9567 register_local_specialization (TREE_TYPE (pack), parm);
9571 template_parm_level_and_index (parm, &level, &idx);
9573 /* Update the corresponding argument. */
9574 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
9575 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
9578 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
9582 if (saved_local_specializations)
9584 htab_delete (local_specializations);
9585 local_specializations = saved_local_specializations;
9591 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
9592 TMPL. We do this using DECL_PARM_INDEX, which should work even with
9593 parameter packs; all parms generated from a function parameter pack will
9594 have the same DECL_PARM_INDEX. */
9597 get_pattern_parm (tree parm, tree tmpl)
9599 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
9602 if (DECL_ARTIFICIAL (parm))
9604 for (patparm = DECL_ARGUMENTS (pattern);
9605 patparm; patparm = DECL_CHAIN (patparm))
9606 if (DECL_ARTIFICIAL (patparm)
9607 && DECL_NAME (parm) == DECL_NAME (patparm))
9612 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
9613 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
9614 gcc_assert (DECL_PARM_INDEX (patparm)
9615 == DECL_PARM_INDEX (parm));
9621 /* Substitute ARGS into the vector or list of template arguments T. */
9624 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9627 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9630 if (t == error_mark_node)
9631 return error_mark_node;
9633 len = TREE_VEC_LENGTH (t);
9634 elts = XALLOCAVEC (tree, len);
9636 for (i = 0; i < len; i++)
9638 tree orig_arg = TREE_VEC_ELT (t, i);
9641 if (TREE_CODE (orig_arg) == TREE_VEC)
9642 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9643 else if (PACK_EXPANSION_P (orig_arg))
9645 /* Substitute into an expansion expression. */
9646 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9648 if (TREE_CODE (new_arg) == TREE_VEC)
9649 /* Add to the expanded length adjustment the number of
9650 expanded arguments. We subtract one from this
9651 measurement, because the argument pack expression
9652 itself is already counted as 1 in
9653 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9654 the argument pack is empty. */
9655 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9657 else if (ARGUMENT_PACK_P (orig_arg))
9659 /* Substitute into each of the arguments. */
9660 new_arg = TYPE_P (orig_arg)
9661 ? cxx_make_type (TREE_CODE (orig_arg))
9662 : make_node (TREE_CODE (orig_arg));
9664 SET_ARGUMENT_PACK_ARGS (
9666 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9667 args, complain, in_decl));
9669 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9670 new_arg = error_mark_node;
9672 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9673 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9675 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9677 if (TREE_TYPE (new_arg) == error_mark_node)
9678 new_arg = error_mark_node;
9682 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9684 if (new_arg == error_mark_node)
9685 return error_mark_node;
9688 if (new_arg != orig_arg)
9695 /* Make space for the expanded arguments coming from template
9697 t = make_tree_vec (len + expanded_len_adjust);
9698 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9699 arguments for a member template.
9700 In that case each TREE_VEC in ORIG_T represents a level of template
9701 arguments, and ORIG_T won't carry any non defaulted argument count.
9702 It will rather be the nested TREE_VECs that will carry one.
9703 In other words, ORIG_T carries a non defaulted argument count only
9704 if it doesn't contain any nested TREE_VEC. */
9705 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9707 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9708 count += expanded_len_adjust;
9709 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9711 for (i = 0, out = 0; i < len; i++)
9713 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9714 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9715 && TREE_CODE (elts[i]) == TREE_VEC)
9719 /* Now expand the template argument pack "in place". */
9720 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9721 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9725 TREE_VEC_ELT (t, out) = elts[i];
9733 /* Return the result of substituting ARGS into the template parameters
9734 given by PARMS. If there are m levels of ARGS and m + n levels of
9735 PARMS, then the result will contain n levels of PARMS. For
9736 example, if PARMS is `template <class T> template <class U>
9737 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9738 result will be `template <int*, double, class V>'. */
9741 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9746 /* When substituting into a template, we must set
9747 PROCESSING_TEMPLATE_DECL as the template parameters may be
9748 dependent if they are based on one-another, and the dependency
9749 predicates are short-circuit outside of templates. */
9750 ++processing_template_decl;
9752 for (new_parms = &r;
9753 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9754 new_parms = &(TREE_CHAIN (*new_parms)),
9755 parms = TREE_CHAIN (parms))
9758 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9761 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9765 if (parms == error_mark_node)
9768 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9770 if (tuple == error_mark_node)
9773 TREE_VEC_ELT (new_vec, i) =
9774 tsubst_template_parm (tuple, args, complain);
9778 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9779 - TMPL_ARGS_DEPTH (args)),
9780 new_vec, NULL_TREE);
9783 --processing_template_decl;
9788 /* Return the result of substituting ARGS into one template parameter
9789 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9790 parameter and which TREE_PURPOSE is the default argument of the
9791 template parameter. */
9794 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9796 tree default_value, parm_decl;
9798 if (args == NULL_TREE
9800 || t == error_mark_node)
9803 gcc_assert (TREE_CODE (t) == TREE_LIST);
9805 default_value = TREE_PURPOSE (t);
9806 parm_decl = TREE_VALUE (t);
9808 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9809 if (TREE_CODE (parm_decl) == PARM_DECL
9810 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9811 parm_decl = error_mark_node;
9812 default_value = tsubst_template_arg (default_value, args,
9813 complain, NULL_TREE);
9815 return build_tree_list (default_value, parm_decl);
9818 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9819 type T. If T is not an aggregate or enumeration type, it is
9820 handled as if by tsubst. IN_DECL is as for tsubst. If
9821 ENTERING_SCOPE is nonzero, T is the context for a template which
9822 we are presently tsubst'ing. Return the substituted value. */
9825 tsubst_aggr_type (tree t,
9827 tsubst_flags_t complain,
9834 switch (TREE_CODE (t))
9837 if (TYPE_PTRMEMFUNC_P (t))
9838 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9840 /* Else fall through. */
9843 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9848 int saved_unevaluated_operand;
9849 int saved_inhibit_evaluation_warnings;
9851 /* In "sizeof(X<I>)" we need to evaluate "I". */
9852 saved_unevaluated_operand = cp_unevaluated_operand;
9853 cp_unevaluated_operand = 0;
9854 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9855 c_inhibit_evaluation_warnings = 0;
9857 /* First, determine the context for the type we are looking
9859 context = TYPE_CONTEXT (t);
9860 if (context && TYPE_P (context))
9862 context = tsubst_aggr_type (context, args, complain,
9863 in_decl, /*entering_scope=*/1);
9864 /* If context is a nested class inside a class template,
9865 it may still need to be instantiated (c++/33959). */
9866 context = complete_type (context);
9869 /* Then, figure out what arguments are appropriate for the
9870 type we are trying to find. For example, given:
9872 template <class T> struct S;
9873 template <class T, class U> void f(T, U) { S<U> su; }
9875 and supposing that we are instantiating f<int, double>,
9876 then our ARGS will be {int, double}, but, when looking up
9877 S we only want {double}. */
9878 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9880 if (argvec == error_mark_node)
9881 r = error_mark_node;
9884 r = lookup_template_class (t, argvec, in_decl, context,
9885 entering_scope, complain);
9886 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9889 cp_unevaluated_operand = saved_unevaluated_operand;
9890 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9895 /* This is not a template type, so there's nothing to do. */
9899 return tsubst (t, args, complain, in_decl);
9903 /* Substitute into the default argument ARG (a default argument for
9904 FN), which has the indicated TYPE. */
9907 tsubst_default_argument (tree fn, tree type, tree arg)
9909 tree saved_class_ptr = NULL_TREE;
9910 tree saved_class_ref = NULL_TREE;
9912 /* This can happen in invalid code. */
9913 if (TREE_CODE (arg) == DEFAULT_ARG)
9916 /* This default argument came from a template. Instantiate the
9917 default argument here, not in tsubst. In the case of
9926 we must be careful to do name lookup in the scope of S<T>,
9927 rather than in the current class. */
9928 push_access_scope (fn);
9929 /* The "this" pointer is not valid in a default argument. */
9932 saved_class_ptr = current_class_ptr;
9933 cp_function_chain->x_current_class_ptr = NULL_TREE;
9934 saved_class_ref = current_class_ref;
9935 cp_function_chain->x_current_class_ref = NULL_TREE;
9938 push_deferring_access_checks(dk_no_deferred);
9939 /* The default argument expression may cause implicitly defined
9940 member functions to be synthesized, which will result in garbage
9941 collection. We must treat this situation as if we were within
9942 the body of function so as to avoid collecting live data on the
9945 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9946 tf_warning_or_error, NULL_TREE,
9947 /*integral_constant_expression_p=*/false);
9949 pop_deferring_access_checks();
9951 /* Restore the "this" pointer. */
9954 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9955 cp_function_chain->x_current_class_ref = saved_class_ref;
9958 /* Make sure the default argument is reasonable. */
9959 arg = check_default_argument (type, arg);
9961 pop_access_scope (fn);
9966 /* Substitute into all the default arguments for FN. */
9969 tsubst_default_arguments (tree fn)
9974 tmpl_args = DECL_TI_ARGS (fn);
9976 /* If this function is not yet instantiated, we certainly don't need
9977 its default arguments. */
9978 if (uses_template_parms (tmpl_args))
9980 /* Don't do this again for clones. */
9981 if (DECL_CLONED_FUNCTION_P (fn))
9984 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9986 arg = TREE_CHAIN (arg))
9987 if (TREE_PURPOSE (arg))
9988 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9990 TREE_PURPOSE (arg));
9993 /* Substitute the ARGS into the T, which is a _DECL. Return the
9994 result of the substitution. Issue error and warning messages under
9995 control of COMPLAIN. */
9998 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
10000 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
10001 location_t saved_loc;
10002 tree r = NULL_TREE;
10004 hashval_t hash = 0;
10006 /* Set the filename and linenumber to improve error-reporting. */
10007 saved_loc = input_location;
10008 input_location = DECL_SOURCE_LOCATION (t);
10010 switch (TREE_CODE (t))
10012 case TEMPLATE_DECL:
10014 /* We can get here when processing a member function template,
10015 member class template, or template template parameter. */
10016 tree decl = DECL_TEMPLATE_RESULT (t);
10021 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10023 /* Template template parameter is treated here. */
10024 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10025 if (new_type == error_mark_node)
10026 RETURN (error_mark_node);
10029 DECL_CHAIN (r) = NULL_TREE;
10030 TREE_TYPE (r) = new_type;
10031 DECL_TEMPLATE_RESULT (r)
10032 = build_decl (DECL_SOURCE_LOCATION (decl),
10033 TYPE_DECL, DECL_NAME (decl), new_type);
10034 DECL_TEMPLATE_PARMS (r)
10035 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10037 TYPE_NAME (new_type) = r;
10041 /* We might already have an instance of this template.
10042 The ARGS are for the surrounding class type, so the
10043 full args contain the tsubst'd args for the context,
10044 plus the innermost args from the template decl. */
10045 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
10046 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
10047 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
10048 /* Because this is a template, the arguments will still be
10049 dependent, even after substitution. If
10050 PROCESSING_TEMPLATE_DECL is not set, the dependency
10051 predicates will short-circuit. */
10052 ++processing_template_decl;
10053 full_args = tsubst_template_args (tmpl_args, args,
10054 complain, in_decl);
10055 --processing_template_decl;
10056 if (full_args == error_mark_node)
10057 RETURN (error_mark_node);
10059 /* If this is a default template template argument,
10060 tsubst might not have changed anything. */
10061 if (full_args == tmpl_args)
10064 hash = hash_tmpl_and_args (t, full_args);
10065 spec = retrieve_specialization (t, full_args, hash);
10066 if (spec != NULL_TREE)
10072 /* Make a new template decl. It will be similar to the
10073 original, but will record the current template arguments.
10074 We also create a new function declaration, which is just
10075 like the old one, but points to this new template, rather
10076 than the old one. */
10078 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
10079 DECL_CHAIN (r) = NULL_TREE;
10081 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10083 if (TREE_CODE (decl) == TYPE_DECL
10084 && !TYPE_DECL_ALIAS_P (decl))
10087 ++processing_template_decl;
10088 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10089 --processing_template_decl;
10090 if (new_type == error_mark_node)
10091 RETURN (error_mark_node);
10093 TREE_TYPE (r) = new_type;
10094 CLASSTYPE_TI_TEMPLATE (new_type) = r;
10095 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
10096 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
10097 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
10102 ++processing_template_decl;
10103 new_decl = tsubst (decl, args, complain, in_decl);
10104 --processing_template_decl;
10105 if (new_decl == error_mark_node)
10106 RETURN (error_mark_node);
10108 DECL_TEMPLATE_RESULT (r) = new_decl;
10109 DECL_TI_TEMPLATE (new_decl) = r;
10110 TREE_TYPE (r) = TREE_TYPE (new_decl);
10111 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
10112 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
10115 SET_DECL_IMPLICIT_INSTANTIATION (r);
10116 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
10117 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
10119 /* The template parameters for this new template are all the
10120 template parameters for the old template, except the
10121 outermost level of parameters. */
10122 DECL_TEMPLATE_PARMS (r)
10123 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10126 if (PRIMARY_TEMPLATE_P (t))
10127 DECL_PRIMARY_TEMPLATE (r) = r;
10129 if (TREE_CODE (decl) != TYPE_DECL)
10130 /* Record this non-type partial instantiation. */
10131 register_specialization (r, t,
10132 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
10137 case FUNCTION_DECL:
10140 tree argvec = NULL_TREE;
10148 /* Nobody should be tsubst'ing into non-template functions. */
10149 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
10151 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
10156 /* If T is not dependent, just return it. We have to
10157 increment PROCESSING_TEMPLATE_DECL because
10158 value_dependent_expression_p assumes that nothing is
10159 dependent when PROCESSING_TEMPLATE_DECL is zero. */
10160 ++processing_template_decl;
10161 dependent_p = value_dependent_expression_p (t);
10162 --processing_template_decl;
10166 /* Calculate the most general template of which R is a
10167 specialization, and the complete set of arguments used to
10169 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
10170 argvec = tsubst_template_args (DECL_TI_ARGS
10171 (DECL_TEMPLATE_RESULT
10172 (DECL_TI_TEMPLATE (t))),
10173 args, complain, in_decl);
10174 if (argvec == error_mark_node)
10175 RETURN (error_mark_node);
10177 /* Check to see if we already have this specialization. */
10178 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10179 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10187 /* We can see more levels of arguments than parameters if
10188 there was a specialization of a member template, like
10191 template <class T> struct S { template <class U> void f(); }
10192 template <> template <class U> void S<int>::f(U);
10194 Here, we'll be substituting into the specialization,
10195 because that's where we can find the code we actually
10196 want to generate, but we'll have enough arguments for
10197 the most general template.
10199 We also deal with the peculiar case:
10201 template <class T> struct S {
10202 template <class U> friend void f();
10204 template <class U> void f() {}
10206 template void f<double>();
10208 Here, the ARGS for the instantiation of will be {int,
10209 double}. But, we only need as many ARGS as there are
10210 levels of template parameters in CODE_PATTERN. We are
10211 careful not to get fooled into reducing the ARGS in
10214 template <class T> struct S { template <class U> void f(U); }
10215 template <class T> template <> void S<T>::f(int) {}
10217 which we can spot because the pattern will be a
10218 specialization in this case. */
10219 args_depth = TMPL_ARGS_DEPTH (args);
10221 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
10222 if (args_depth > parms_depth
10223 && !DECL_TEMPLATE_SPECIALIZATION (t))
10224 args = get_innermost_template_args (args, parms_depth);
10228 /* This special case arises when we have something like this:
10230 template <class T> struct S {
10231 friend void f<int>(int, double);
10234 Here, the DECL_TI_TEMPLATE for the friend declaration
10235 will be an IDENTIFIER_NODE. We are being called from
10236 tsubst_friend_function, and we want only to create a
10237 new decl (R) with appropriate types so that we can call
10238 determine_specialization. */
10239 gen_tmpl = NULL_TREE;
10242 if (DECL_CLASS_SCOPE_P (t))
10244 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
10248 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
10249 complain, t, /*entering_scope=*/1);
10254 ctx = DECL_CONTEXT (t);
10256 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10257 if (type == error_mark_node)
10258 RETURN (error_mark_node);
10260 /* We do NOT check for matching decls pushed separately at this
10261 point, as they may not represent instantiations of this
10262 template, and in any case are considered separate under the
10265 DECL_USE_TEMPLATE (r) = 0;
10266 TREE_TYPE (r) = type;
10267 /* Clear out the mangled name and RTL for the instantiation. */
10268 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10269 SET_DECL_RTL (r, NULL);
10270 /* Leave DECL_INITIAL set on deleted instantiations. */
10271 if (!DECL_DELETED_FN (r))
10272 DECL_INITIAL (r) = NULL_TREE;
10273 DECL_CONTEXT (r) = ctx;
10275 if (member && DECL_CONV_FN_P (r))
10276 /* Type-conversion operator. Reconstruct the name, in
10277 case it's the name of one of the template's parameters. */
10278 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
10280 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
10282 DECL_RESULT (r) = NULL_TREE;
10284 TREE_STATIC (r) = 0;
10285 TREE_PUBLIC (r) = TREE_PUBLIC (t);
10286 DECL_EXTERNAL (r) = 1;
10287 /* If this is an instantiation of a function with internal
10288 linkage, we already know what object file linkage will be
10289 assigned to the instantiation. */
10290 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
10291 DECL_DEFER_OUTPUT (r) = 0;
10292 DECL_CHAIN (r) = NULL_TREE;
10293 DECL_PENDING_INLINE_INFO (r) = 0;
10294 DECL_PENDING_INLINE_P (r) = 0;
10295 DECL_SAVED_TREE (r) = NULL_TREE;
10296 DECL_STRUCT_FUNCTION (r) = NULL;
10298 /* We'll re-clone as appropriate in instantiate_template. */
10299 DECL_CLONED_FUNCTION (r) = NULL_TREE;
10301 /* If we aren't complaining now, return on error before we register
10302 the specialization so that we'll complain eventually. */
10303 if ((complain & tf_error) == 0
10304 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10305 && !grok_op_properties (r, /*complain=*/false))
10306 RETURN (error_mark_node);
10308 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
10309 this in the special friend case mentioned above where
10310 GEN_TMPL is NULL. */
10313 DECL_TEMPLATE_INFO (r)
10314 = build_template_info (gen_tmpl, argvec);
10315 SET_DECL_IMPLICIT_INSTANTIATION (r);
10316 register_specialization (r, gen_tmpl, argvec, false, hash);
10318 /* We're not supposed to instantiate default arguments
10319 until they are called, for a template. But, for a
10322 template <class T> void f ()
10323 { extern void g(int i = T()); }
10325 we should do the substitution when the template is
10326 instantiated. We handle the member function case in
10327 instantiate_class_template since the default arguments
10328 might refer to other members of the class. */
10330 && !PRIMARY_TEMPLATE_P (gen_tmpl)
10331 && !uses_template_parms (argvec))
10332 tsubst_default_arguments (r);
10335 DECL_TEMPLATE_INFO (r) = NULL_TREE;
10337 /* Copy the list of befriending classes. */
10338 for (friends = &DECL_BEFRIENDING_CLASSES (r);
10340 friends = &TREE_CHAIN (*friends))
10342 *friends = copy_node (*friends);
10343 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
10348 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
10350 maybe_retrofit_in_chrg (r);
10351 if (DECL_CONSTRUCTOR_P (r))
10352 grok_ctor_properties (ctx, r);
10353 /* If this is an instantiation of a member template, clone it.
10354 If it isn't, that'll be handled by
10355 clone_constructors_and_destructors. */
10356 if (PRIMARY_TEMPLATE_P (gen_tmpl))
10357 clone_function_decl (r, /*update_method_vec_p=*/0);
10359 else if ((complain & tf_error) != 0
10360 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10361 && !grok_op_properties (r, /*complain=*/true))
10362 RETURN (error_mark_node);
10364 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
10365 SET_DECL_FRIEND_CONTEXT (r,
10366 tsubst (DECL_FRIEND_CONTEXT (t),
10367 args, complain, in_decl));
10369 /* Possibly limit visibility based on template args. */
10370 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10371 if (DECL_VISIBILITY_SPECIFIED (t))
10373 DECL_VISIBILITY_SPECIFIED (r) = 0;
10374 DECL_ATTRIBUTES (r)
10375 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10377 determine_visibility (r);
10378 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
10379 && !processing_template_decl)
10380 defaulted_late_check (r);
10382 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10383 args, complain, in_decl);
10389 tree type = NULL_TREE;
10391 tree expanded_types = NULL_TREE;
10392 tree prev_r = NULL_TREE;
10393 tree first_r = NULL_TREE;
10395 if (FUNCTION_PARAMETER_PACK_P (t))
10397 /* If there is a local specialization that isn't a
10398 parameter pack, it means that we're doing a "simple"
10399 substitution from inside tsubst_pack_expansion. Just
10400 return the local specialization (which will be a single
10402 tree spec = retrieve_local_specialization (t);
10404 && TREE_CODE (spec) == PARM_DECL
10405 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
10408 /* Expand the TYPE_PACK_EXPANSION that provides the types for
10409 the parameters in this function parameter pack. */
10410 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
10411 complain, in_decl);
10412 if (TREE_CODE (expanded_types) == TREE_VEC)
10414 len = TREE_VEC_LENGTH (expanded_types);
10416 /* Zero-length parameter packs are boring. Just substitute
10419 RETURN (tsubst (TREE_CHAIN (t), args, complain,
10424 /* All we did was update the type. Make a note of that. */
10425 type = expanded_types;
10426 expanded_types = NULL_TREE;
10430 /* Loop through all of the parameter's we'll build. When T is
10431 a function parameter pack, LEN is the number of expanded
10432 types in EXPANDED_TYPES; otherwise, LEN is 1. */
10434 for (i = 0; i < len; ++i)
10438 if (DECL_TEMPLATE_PARM_P (t))
10439 SET_DECL_TEMPLATE_PARM_P (r);
10441 if (expanded_types)
10442 /* We're on the Ith parameter of the function parameter
10445 /* An argument of a function parameter pack is not a parameter
10447 FUNCTION_PARAMETER_PACK_P (r) = false;
10449 /* Get the Ith type. */
10450 type = TREE_VEC_ELT (expanded_types, i);
10453 /* Rename the parameter to include the index. */
10455 make_ith_pack_parameter_name (DECL_NAME (r), i);
10458 /* We're dealing with a normal parameter. */
10459 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10461 type = type_decays_to (type);
10462 TREE_TYPE (r) = type;
10463 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10465 if (DECL_INITIAL (r))
10467 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
10468 DECL_INITIAL (r) = TREE_TYPE (r);
10470 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
10471 complain, in_decl);
10474 DECL_CONTEXT (r) = NULL_TREE;
10476 if (!DECL_TEMPLATE_PARM_P (r))
10477 DECL_ARG_TYPE (r) = type_passed_as (type);
10479 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10480 args, complain, in_decl);
10482 /* Keep track of the first new parameter we
10483 generate. That's what will be returned to the
10488 /* Build a proper chain of parameters when substituting
10489 into a function parameter pack. */
10491 DECL_CHAIN (prev_r) = r;
10494 if (DECL_CHAIN (t))
10495 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
10496 complain, DECL_CHAIN (t));
10498 /* FIRST_R contains the start of the chain we've built. */
10508 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10509 if (type == error_mark_node)
10510 RETURN (error_mark_node);
10511 TREE_TYPE (r) = type;
10512 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10514 if (DECL_C_BIT_FIELD (r))
10515 /* For bit-fields, DECL_INITIAL gives the number of bits. For
10516 non-bit-fields DECL_INITIAL is a non-static data member
10517 initializer, which gets deferred instantiation. */
10519 = tsubst_expr (DECL_INITIAL (t), args,
10521 /*integral_constant_expression_p=*/true);
10522 else if (DECL_INITIAL (t))
10524 /* Set up DECL_TEMPLATE_INFO so that we can get at the
10525 NSDMI in perform_member_init. Still set DECL_INITIAL
10526 so that we know there is one. */
10527 DECL_INITIAL (r) = void_zero_node;
10528 gcc_assert (DECL_LANG_SPECIFIC (r) == NULL);
10529 retrofit_lang_decl (r);
10530 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10532 /* We don't have to set DECL_CONTEXT here; it is set by
10533 finish_member_declaration. */
10534 DECL_CHAIN (r) = NULL_TREE;
10535 if (VOID_TYPE_P (type))
10536 error ("instantiation of %q+D as type %qT", r, type);
10538 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10539 args, complain, in_decl);
10544 /* We reach here only for member using decls. */
10545 if (DECL_DEPENDENT_P (t))
10547 r = do_class_using_decl
10548 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
10549 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
10551 r = error_mark_node;
10554 TREE_PROTECTED (r) = TREE_PROTECTED (t);
10555 TREE_PRIVATE (r) = TREE_PRIVATE (t);
10561 DECL_CHAIN (r) = NULL_TREE;
10568 tree argvec = NULL_TREE;
10569 tree gen_tmpl = NULL_TREE;
10571 tree tmpl = NULL_TREE;
10573 tree type = NULL_TREE;
10576 if (TREE_CODE (t) == TYPE_DECL
10577 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
10579 /* If this is the canonical decl, we don't have to
10580 mess with instantiations, and often we can't (for
10581 typename, template type parms and such). Note that
10582 TYPE_NAME is not correct for the above test if
10583 we've copied the type for a typedef. */
10584 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10585 if (type == error_mark_node)
10586 RETURN (error_mark_node);
10587 r = TYPE_NAME (type);
10591 /* Check to see if we already have the specialization we
10594 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
10596 /* T is a static data member or namespace-scope entity.
10597 We have to substitute into namespace-scope variables
10598 (even though such entities are never templates) because
10601 template <class T> void f() { extern T t; }
10603 where the entity referenced is not known until
10604 instantiation time. */
10606 ctx = DECL_CONTEXT (t);
10607 if (DECL_CLASS_SCOPE_P (t))
10609 ctx = tsubst_aggr_type (ctx, args,
10611 in_decl, /*entering_scope=*/1);
10612 /* If CTX is unchanged, then T is in fact the
10613 specialization we want. That situation occurs when
10614 referencing a static data member within in its own
10615 class. We can use pointer equality, rather than
10616 same_type_p, because DECL_CONTEXT is always
10618 if (ctx == DECL_CONTEXT (t)
10619 && (TREE_CODE (t) != TYPE_DECL
10620 /* ... unless T is a member template; in which
10621 case our caller can be willing to create a
10622 specialization of that template represented
10624 || !(DECL_TI_TEMPLATE (t)
10625 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (t)))))
10631 tmpl = DECL_TI_TEMPLATE (t);
10632 gen_tmpl = most_general_template (tmpl);
10633 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
10634 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10635 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10640 /* A local variable. */
10642 /* Subsequent calls to pushdecl will fill this in. */
10644 spec = retrieve_local_specialization (t);
10646 /* If we already have the specialization we need, there is
10647 nothing more to do. */
10654 /* Create a new node for the specialization we need. */
10656 if (type == NULL_TREE)
10658 if (is_typedef_decl (t))
10659 type = DECL_ORIGINAL_TYPE (t);
10661 type = TREE_TYPE (t);
10662 if (TREE_CODE (t) == VAR_DECL
10663 && VAR_HAD_UNKNOWN_BOUND (t)
10664 && type != error_mark_node)
10665 type = strip_array_domain (type);
10666 type = tsubst (type, args, complain, in_decl);
10668 if (TREE_CODE (r) == VAR_DECL)
10670 /* Even if the original location is out of scope, the
10671 newly substituted one is not. */
10672 DECL_DEAD_FOR_LOCAL (r) = 0;
10673 DECL_INITIALIZED_P (r) = 0;
10674 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10675 if (type == error_mark_node)
10676 RETURN (error_mark_node);
10677 if (TREE_CODE (type) == FUNCTION_TYPE)
10679 /* It may seem that this case cannot occur, since:
10684 declares a function, not a variable. However:
10687 template <typename T> void g() { T t; }
10688 template void g<f>();
10690 is an attempt to declare a variable with function
10692 error ("variable %qD has function type",
10693 /* R is not yet sufficiently initialized, so we
10694 just use its name. */
10696 RETURN (error_mark_node);
10698 type = complete_type (type);
10699 /* Wait until cp_finish_decl to set this again, to handle
10700 circular dependency (template/instantiate6.C). */
10701 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10702 type = check_var_type (DECL_NAME (r), type);
10704 if (DECL_HAS_VALUE_EXPR_P (t))
10706 tree ve = DECL_VALUE_EXPR (t);
10707 ve = tsubst_expr (ve, args, complain, in_decl,
10708 /*constant_expression_p=*/false);
10709 if (REFERENCE_REF_P (ve))
10711 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
10712 ve = TREE_OPERAND (ve, 0);
10714 SET_DECL_VALUE_EXPR (r, ve);
10717 else if (DECL_SELF_REFERENCE_P (t))
10718 SET_DECL_SELF_REFERENCE_P (r);
10719 TREE_TYPE (r) = type;
10720 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10721 DECL_CONTEXT (r) = ctx;
10722 /* Clear out the mangled name and RTL for the instantiation. */
10723 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10724 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10725 SET_DECL_RTL (r, NULL);
10726 /* The initializer must not be expanded until it is required;
10727 see [temp.inst]. */
10728 DECL_INITIAL (r) = NULL_TREE;
10729 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10730 SET_DECL_RTL (r, NULL);
10731 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10732 if (TREE_CODE (r) == VAR_DECL)
10734 /* Possibly limit visibility based on template args. */
10735 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10736 if (DECL_VISIBILITY_SPECIFIED (t))
10738 DECL_VISIBILITY_SPECIFIED (r) = 0;
10739 DECL_ATTRIBUTES (r)
10740 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10742 determine_visibility (r);
10747 /* A static data member declaration is always marked
10748 external when it is declared in-class, even if an
10749 initializer is present. We mimic the non-template
10750 processing here. */
10751 DECL_EXTERNAL (r) = 1;
10753 register_specialization (r, gen_tmpl, argvec, false, hash);
10754 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10755 SET_DECL_IMPLICIT_INSTANTIATION (r);
10757 else if (cp_unevaluated_operand)
10759 /* We're substituting this var in a decltype outside of its
10760 scope, such as for a lambda return type. Don't add it to
10761 local_specializations, do perform auto deduction. */
10762 tree auto_node = type_uses_auto (type);
10766 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10767 /*constant_expression_p=*/false);
10768 init = resolve_nondeduced_context (init);
10769 TREE_TYPE (r) = type
10770 = do_auto_deduction (type, init, auto_node);
10774 register_local_specialization (r, t);
10776 DECL_CHAIN (r) = NULL_TREE;
10778 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10780 args, complain, in_decl);
10782 /* Preserve a typedef that names a type. */
10783 if (is_typedef_decl (r))
10785 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10786 set_underlying_type (r);
10789 layout_decl (r, 0);
10794 gcc_unreachable ();
10799 /* Restore the file and line information. */
10800 input_location = saved_loc;
10805 /* Substitute into the ARG_TYPES of a function type. */
10808 tsubst_arg_types (tree arg_types,
10810 tsubst_flags_t complain,
10813 tree remaining_arg_types;
10814 tree type = NULL_TREE;
10816 tree expanded_args = NULL_TREE;
10819 if (!arg_types || arg_types == void_list_node)
10822 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10823 args, complain, in_decl);
10824 if (remaining_arg_types == error_mark_node)
10825 return error_mark_node;
10827 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10829 /* For a pack expansion, perform substitution on the
10830 entire expression. Later on, we'll handle the arguments
10832 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10833 args, complain, in_decl);
10835 if (TREE_CODE (expanded_args) == TREE_VEC)
10836 /* So that we'll spin through the parameters, one by one. */
10837 i = TREE_VEC_LENGTH (expanded_args);
10840 /* We only partially substituted into the parameter
10841 pack. Our type is TYPE_PACK_EXPANSION. */
10842 type = expanded_args;
10843 expanded_args = NULL_TREE;
10851 type = TREE_VEC_ELT (expanded_args, i);
10853 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10855 if (type == error_mark_node)
10856 return error_mark_node;
10857 if (VOID_TYPE_P (type))
10859 if (complain & tf_error)
10861 error ("invalid parameter type %qT", type);
10863 error ("in declaration %q+D", in_decl);
10865 return error_mark_node;
10868 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10869 top-level qualifiers as required. */
10870 type = cv_unqualified (type_decays_to (type));
10872 /* We do not substitute into default arguments here. The standard
10873 mandates that they be instantiated only when needed, which is
10874 done in build_over_call. */
10875 default_arg = TREE_PURPOSE (arg_types);
10877 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10879 /* We've instantiated a template before its default arguments
10880 have been parsed. This can happen for a nested template
10881 class, and is not an error unless we require the default
10882 argument in a call of this function. */
10883 remaining_arg_types =
10884 tree_cons (default_arg, type, remaining_arg_types);
10885 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10886 remaining_arg_types);
10889 remaining_arg_types =
10890 hash_tree_cons (default_arg, type, remaining_arg_types);
10893 return remaining_arg_types;
10896 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10897 *not* handle the exception-specification for FNTYPE, because the
10898 initial substitution of explicitly provided template parameters
10899 during argument deduction forbids substitution into the
10900 exception-specification:
10904 All references in the function type of the function template to the
10905 corresponding template parameters are replaced by the specified tem-
10906 plate argument values. If a substitution in a template parameter or
10907 in the function type of the function template results in an invalid
10908 type, type deduction fails. [Note: The equivalent substitution in
10909 exception specifications is done only when the function is instanti-
10910 ated, at which point a program is ill-formed if the substitution
10911 results in an invalid type.] */
10914 tsubst_function_type (tree t,
10916 tsubst_flags_t complain,
10923 /* The TYPE_CONTEXT is not used for function/method types. */
10924 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10926 /* Substitute the return type. */
10927 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10928 if (return_type == error_mark_node)
10929 return error_mark_node;
10930 /* The standard does not presently indicate that creation of a
10931 function type with an invalid return type is a deduction failure.
10932 However, that is clearly analogous to creating an array of "void"
10933 or a reference to a reference. This is core issue #486. */
10934 if (TREE_CODE (return_type) == ARRAY_TYPE
10935 || TREE_CODE (return_type) == FUNCTION_TYPE)
10937 if (complain & tf_error)
10939 if (TREE_CODE (return_type) == ARRAY_TYPE)
10940 error ("function returning an array");
10942 error ("function returning a function");
10944 return error_mark_node;
10947 /* Substitute the argument types. */
10948 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10949 complain, in_decl);
10950 if (arg_types == error_mark_node)
10951 return error_mark_node;
10953 /* Construct a new type node and return it. */
10954 if (TREE_CODE (t) == FUNCTION_TYPE)
10956 fntype = build_function_type (return_type, arg_types);
10957 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10961 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10962 if (! MAYBE_CLASS_TYPE_P (r))
10966 Type deduction may fail for any of the following
10969 -- Attempting to create "pointer to member of T" when T
10970 is not a class type. */
10971 if (complain & tf_error)
10972 error ("creating pointer to member function of non-class type %qT",
10974 return error_mark_node;
10977 fntype = build_method_type_directly (r, return_type,
10978 TREE_CHAIN (arg_types));
10980 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10985 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10986 ARGS into that specification, and return the substituted
10987 specification. If there is no specification, return NULL_TREE. */
10990 tsubst_exception_specification (tree fntype,
10992 tsubst_flags_t complain,
10999 specs = TYPE_RAISES_EXCEPTIONS (fntype);
11000 new_specs = NULL_TREE;
11001 if (specs && TREE_PURPOSE (specs))
11003 /* A noexcept-specifier. */
11004 tree expr = TREE_PURPOSE (specs);
11005 if (expr == boolean_true_node || expr == boolean_false_node)
11009 /* Defer instantiation of noexcept-specifiers to avoid
11010 excessive instantiations (c++/49107). */
11011 new_specs = make_node (DEFERRED_NOEXCEPT);
11012 if (DEFERRED_NOEXCEPT_SPEC_P (specs))
11014 /* We already partially instantiated this member template,
11015 so combine the new args with the old. */
11016 DEFERRED_NOEXCEPT_PATTERN (new_specs)
11017 = DEFERRED_NOEXCEPT_PATTERN (expr);
11018 DEFERRED_NOEXCEPT_ARGS (new_specs)
11019 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args);
11023 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr;
11024 DEFERRED_NOEXCEPT_ARGS (new_specs) = args;
11028 new_specs = tsubst_copy_and_build
11029 (expr, args, complain, in_decl, /*function_p=*/false,
11030 /*integral_constant_expression_p=*/true);
11031 new_specs = build_noexcept_spec (new_specs, complain);
11035 if (! TREE_VALUE (specs))
11042 tree expanded_specs = NULL_TREE;
11044 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
11046 /* Expand the pack expansion type. */
11047 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
11051 if (expanded_specs == error_mark_node)
11052 return error_mark_node;
11053 else if (TREE_CODE (expanded_specs) == TREE_VEC)
11054 len = TREE_VEC_LENGTH (expanded_specs);
11057 /* We're substituting into a member template, so
11058 we got a TYPE_PACK_EXPANSION back. Add that
11059 expansion and move on. */
11060 gcc_assert (TREE_CODE (expanded_specs)
11061 == TYPE_PACK_EXPANSION);
11062 new_specs = add_exception_specifier (new_specs,
11065 specs = TREE_CHAIN (specs);
11070 for (i = 0; i < len; ++i)
11072 if (expanded_specs)
11073 spec = TREE_VEC_ELT (expanded_specs, i);
11075 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
11076 if (spec == error_mark_node)
11078 new_specs = add_exception_specifier (new_specs, spec,
11082 specs = TREE_CHAIN (specs);
11088 /* Take the tree structure T and replace template parameters used
11089 therein with the argument vector ARGS. IN_DECL is an associated
11090 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
11091 Issue error and warning messages under control of COMPLAIN. Note
11092 that we must be relatively non-tolerant of extensions here, in
11093 order to preserve conformance; if we allow substitutions that
11094 should not be allowed, we may allow argument deductions that should
11095 not succeed, and therefore report ambiguous overload situations
11096 where there are none. In theory, we could allow the substitution,
11097 but indicate that it should have failed, and allow our caller to
11098 make sure that the right thing happens, but we don't try to do this
11101 This function is used for dealing with types, decls and the like;
11102 for expressions, use tsubst_expr or tsubst_copy. */
11105 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11107 enum tree_code code;
11108 tree type, r = NULL_TREE;
11110 if (t == NULL_TREE || t == error_mark_node
11111 || t == integer_type_node
11112 || t == void_type_node
11113 || t == char_type_node
11114 || t == unknown_type_node
11115 || TREE_CODE (t) == NAMESPACE_DECL
11116 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
11120 return tsubst_decl (t, args, complain);
11122 if (args == NULL_TREE)
11125 code = TREE_CODE (t);
11127 if (code == IDENTIFIER_NODE)
11128 type = IDENTIFIER_TYPE_VALUE (t);
11130 type = TREE_TYPE (t);
11132 gcc_assert (type != unknown_type_node);
11134 /* Reuse typedefs. We need to do this to handle dependent attributes,
11135 such as attribute aligned. */
11137 && typedef_variant_p (t))
11139 tree decl = TYPE_NAME (t);
11141 if (TYPE_DECL_ALIAS_P (decl)
11142 && DECL_LANG_SPECIFIC (decl)
11143 && DECL_TEMPLATE_INFO (decl)
11144 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl)))
11146 /* DECL represents an alias template and we want to
11147 instantiate it. Let's substitute our arguments for the
11148 template parameters into the declaration and get the
11150 r = tsubst (decl, args, complain, decl);
11152 else if (DECL_CLASS_SCOPE_P (decl)
11153 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
11154 && uses_template_parms (DECL_CONTEXT (decl)))
11156 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11157 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
11158 r = retrieve_specialization (tmpl, gen_args, 0);
11160 else if (DECL_FUNCTION_SCOPE_P (decl)
11161 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
11162 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
11163 r = retrieve_local_specialization (decl);
11165 /* The typedef is from a non-template context. */
11171 r = cp_build_qualified_type_real
11172 (r, cp_type_quals (t) | cp_type_quals (r),
11173 complain | tf_ignore_bad_quals);
11176 /* Else we must be instantiating the typedef, so fall through. */
11180 && code != TYPENAME_TYPE
11181 && code != TEMPLATE_TYPE_PARM
11182 && code != IDENTIFIER_NODE
11183 && code != FUNCTION_TYPE
11184 && code != METHOD_TYPE)
11185 type = tsubst (type, args, complain, in_decl);
11186 if (type == error_mark_node)
11187 return error_mark_node;
11193 case ENUMERAL_TYPE:
11194 return tsubst_aggr_type (t, args, complain, in_decl,
11195 /*entering_scope=*/0);
11198 case IDENTIFIER_NODE:
11209 if (t == integer_type_node)
11212 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
11213 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
11217 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
11219 max = tsubst_expr (omax, args, complain, in_decl,
11220 /*integral_constant_expression_p=*/false);
11222 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
11224 if (TREE_CODE (max) == NOP_EXPR
11225 && TREE_SIDE_EFFECTS (omax)
11226 && !TREE_TYPE (max))
11227 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
11229 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
11230 with TREE_SIDE_EFFECTS that indicates this is not an integral
11231 constant expression. */
11232 if (processing_template_decl
11233 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
11235 gcc_assert (TREE_CODE (max) == NOP_EXPR);
11236 TREE_SIDE_EFFECTS (max) = 1;
11239 return compute_array_index_type (NULL_TREE, max, complain);
11242 case TEMPLATE_TYPE_PARM:
11243 case TEMPLATE_TEMPLATE_PARM:
11244 case BOUND_TEMPLATE_TEMPLATE_PARM:
11245 case TEMPLATE_PARM_INDEX:
11250 tree arg = NULL_TREE;
11254 gcc_assert (TREE_VEC_LENGTH (args) > 0);
11255 template_parm_level_and_index (t, &level, &idx);
11257 levels = TMPL_ARGS_DEPTH (args);
11258 if (level <= levels)
11260 arg = TMPL_ARG (args, level, idx);
11262 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
11263 /* See through ARGUMENT_PACK_SELECT arguments. */
11264 arg = ARGUMENT_PACK_SELECT_ARG (arg);
11267 if (arg == error_mark_node)
11268 return error_mark_node;
11269 else if (arg != NULL_TREE)
11271 if (ARGUMENT_PACK_P (arg))
11272 /* If ARG is an argument pack, we don't actually want to
11273 perform a substitution here, because substitutions
11274 for argument packs are only done
11275 element-by-element. We can get to this point when
11276 substituting the type of a non-type template
11277 parameter pack, when that type actually contains
11278 template parameter packs from an outer template, e.g.,
11280 template<typename... Types> struct A {
11281 template<Types... Values> struct B { };
11285 if (code == TEMPLATE_TYPE_PARM)
11288 gcc_assert (TYPE_P (arg));
11290 quals = cp_type_quals (arg) | cp_type_quals (t);
11292 return cp_build_qualified_type_real
11293 (arg, quals, complain | tf_ignore_bad_quals);
11295 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11297 /* We are processing a type constructed from a
11298 template template parameter. */
11299 tree argvec = tsubst (TYPE_TI_ARGS (t),
11300 args, complain, in_decl);
11301 if (argvec == error_mark_node)
11302 return error_mark_node;
11304 gcc_assert (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
11305 || TREE_CODE (arg) == TEMPLATE_DECL
11306 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
11308 if (TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE)
11309 /* Consider this code:
11311 template <template <class> class Template>
11313 template <class Arg> using Bind = Template<Arg>;
11316 template <template <class> class Template, class Arg>
11317 using Instantiate = Template<Arg>; //#0
11319 template <template <class> class Template,
11322 Instantiate<Internal<Template>::template Bind,
11325 When #1 is parsed, the
11326 BOUND_TEMPLATE_TEMPLATE_PARM representing the
11327 parameter `Template' in #0 matches the
11328 UNBOUND_CLASS_TEMPLATE representing the argument
11329 `Internal<Template>::template Bind'; We then want
11330 to assemble the type `Bind<Argument>' that can't
11331 be fully created right now, because
11332 `Internal<Template>' not being complete, the Bind
11333 template cannot be looked up in that context. So
11334 we need to "store" `Bind<Argument>' for later
11335 when the context of Bind becomes complete. Let's
11336 store that in a TYPENAME_TYPE. */
11337 return make_typename_type (TYPE_CONTEXT (arg),
11338 build_nt (TEMPLATE_ID_EXPR,
11339 TYPE_IDENTIFIER (arg),
11344 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
11345 are resolving nested-types in the signature of a
11346 member function templates. Otherwise ARG is a
11347 TEMPLATE_DECL and is the real template to be
11349 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11350 arg = TYPE_NAME (arg);
11352 r = lookup_template_class (arg,
11354 DECL_CONTEXT (arg),
11355 /*entering_scope=*/0,
11357 return cp_build_qualified_type_real
11358 (r, cp_type_quals (t), complain);
11361 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
11362 return convert_from_reference (unshare_expr (arg));
11366 /* This can happen during the attempted tsubst'ing in
11367 unify. This means that we don't yet have any information
11368 about the template parameter in question. */
11371 /* If we get here, we must have been looking at a parm for a
11372 more deeply nested template. Make a new version of this
11373 template parameter, but with a lower level. */
11376 case TEMPLATE_TYPE_PARM:
11377 case TEMPLATE_TEMPLATE_PARM:
11378 case BOUND_TEMPLATE_TEMPLATE_PARM:
11379 if (cp_type_quals (t))
11381 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
11382 r = cp_build_qualified_type_real
11383 (r, cp_type_quals (t),
11384 complain | (code == TEMPLATE_TYPE_PARM
11385 ? tf_ignore_bad_quals : 0));
11390 TEMPLATE_TYPE_PARM_INDEX (r)
11391 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
11392 r, levels, args, complain);
11393 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
11394 TYPE_MAIN_VARIANT (r) = r;
11395 TYPE_POINTER_TO (r) = NULL_TREE;
11396 TYPE_REFERENCE_TO (r) = NULL_TREE;
11398 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
11399 /* We have reduced the level of the template
11400 template parameter, but not the levels of its
11401 template parameters, so canonical_type_parameter
11402 will not be able to find the canonical template
11403 template parameter for this level. Thus, we
11404 require structural equality checking to compare
11405 TEMPLATE_TEMPLATE_PARMs. */
11406 SET_TYPE_STRUCTURAL_EQUALITY (r);
11407 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
11408 SET_TYPE_STRUCTURAL_EQUALITY (r);
11410 TYPE_CANONICAL (r) = canonical_type_parameter (r);
11412 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11414 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
11415 complain, in_decl);
11416 if (argvec == error_mark_node)
11417 return error_mark_node;
11419 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
11420 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
11425 case TEMPLATE_PARM_INDEX:
11426 r = reduce_template_parm_level (t, type, levels, args, complain);
11430 gcc_unreachable ();
11438 tree purpose, value, chain;
11440 if (t == void_list_node)
11443 purpose = TREE_PURPOSE (t);
11446 purpose = tsubst (purpose, args, complain, in_decl);
11447 if (purpose == error_mark_node)
11448 return error_mark_node;
11450 value = TREE_VALUE (t);
11453 value = tsubst (value, args, complain, in_decl);
11454 if (value == error_mark_node)
11455 return error_mark_node;
11457 chain = TREE_CHAIN (t);
11458 if (chain && chain != void_type_node)
11460 chain = tsubst (chain, args, complain, in_decl);
11461 if (chain == error_mark_node)
11462 return error_mark_node;
11464 if (purpose == TREE_PURPOSE (t)
11465 && value == TREE_VALUE (t)
11466 && chain == TREE_CHAIN (t))
11468 return hash_tree_cons (purpose, value, chain);
11472 /* We should never be tsubsting a binfo. */
11473 gcc_unreachable ();
11476 /* A vector of template arguments. */
11477 gcc_assert (!type);
11478 return tsubst_template_args (t, args, complain, in_decl);
11481 case REFERENCE_TYPE:
11483 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
11488 Type deduction may fail for any of the following
11491 -- Attempting to create a pointer to reference type.
11492 -- Attempting to create a reference to a reference type or
11493 a reference to void.
11495 Core issue 106 says that creating a reference to a reference
11496 during instantiation is no longer a cause for failure. We
11497 only enforce this check in strict C++98 mode. */
11498 if ((TREE_CODE (type) == REFERENCE_TYPE
11499 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
11500 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
11502 static location_t last_loc;
11504 /* We keep track of the last time we issued this error
11505 message to avoid spewing a ton of messages during a
11506 single bad template instantiation. */
11507 if (complain & tf_error
11508 && last_loc != input_location)
11510 if (TREE_CODE (type) == VOID_TYPE)
11511 error ("forming reference to void");
11512 else if (code == POINTER_TYPE)
11513 error ("forming pointer to reference type %qT", type);
11515 error ("forming reference to reference type %qT", type);
11516 last_loc = input_location;
11519 return error_mark_node;
11521 else if (code == POINTER_TYPE)
11523 r = build_pointer_type (type);
11524 if (TREE_CODE (type) == METHOD_TYPE)
11525 r = build_ptrmemfunc_type (r);
11527 else if (TREE_CODE (type) == REFERENCE_TYPE)
11528 /* In C++0x, during template argument substitution, when there is an
11529 attempt to create a reference to a reference type, reference
11530 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
11532 "If a template-argument for a template-parameter T names a type
11533 that is a reference to a type A, an attempt to create the type
11534 'lvalue reference to cv T' creates the type 'lvalue reference to
11535 A,' while an attempt to create the type type rvalue reference to
11536 cv T' creates the type T"
11538 r = cp_build_reference_type
11540 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
11542 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
11543 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
11545 if (r != error_mark_node)
11546 /* Will this ever be needed for TYPE_..._TO values? */
11553 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
11554 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
11558 Type deduction may fail for any of the following
11561 -- Attempting to create "pointer to member of T" when T
11562 is not a class type. */
11563 if (complain & tf_error)
11564 error ("creating pointer to member of non-class type %qT", r);
11565 return error_mark_node;
11567 if (TREE_CODE (type) == REFERENCE_TYPE)
11569 if (complain & tf_error)
11570 error ("creating pointer to member reference type %qT", type);
11571 return error_mark_node;
11573 if (TREE_CODE (type) == VOID_TYPE)
11575 if (complain & tf_error)
11576 error ("creating pointer to member of type void");
11577 return error_mark_node;
11579 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
11580 if (TREE_CODE (type) == FUNCTION_TYPE)
11582 /* The type of the implicit object parameter gets its
11583 cv-qualifiers from the FUNCTION_TYPE. */
11585 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
11586 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
11587 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
11591 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
11595 case FUNCTION_TYPE:
11600 fntype = tsubst_function_type (t, args, complain, in_decl);
11601 if (fntype == error_mark_node)
11602 return error_mark_node;
11604 /* Substitute the exception specification. */
11605 specs = tsubst_exception_specification (t, args, complain,
11606 in_decl, /*defer_ok*/true);
11607 if (specs == error_mark_node)
11608 return error_mark_node;
11610 fntype = build_exception_variant (fntype, specs);
11615 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
11616 if (domain == error_mark_node)
11617 return error_mark_node;
11619 /* As an optimization, we avoid regenerating the array type if
11620 it will obviously be the same as T. */
11621 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
11624 /* These checks should match the ones in grokdeclarator.
11628 The deduction may fail for any of the following reasons:
11630 -- Attempting to create an array with an element type that
11631 is void, a function type, or a reference type, or [DR337]
11632 an abstract class type. */
11633 if (TREE_CODE (type) == VOID_TYPE
11634 || TREE_CODE (type) == FUNCTION_TYPE
11635 || TREE_CODE (type) == REFERENCE_TYPE)
11637 if (complain & tf_error)
11638 error ("creating array of %qT", type);
11639 return error_mark_node;
11641 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
11643 if (complain & tf_error)
11644 error ("creating array of %qT, which is an abstract class type",
11646 return error_mark_node;
11649 r = build_cplus_array_type (type, domain);
11651 if (TYPE_USER_ALIGN (t))
11653 TYPE_ALIGN (r) = TYPE_ALIGN (t);
11654 TYPE_USER_ALIGN (r) = 1;
11660 case TYPENAME_TYPE:
11662 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11663 in_decl, /*entering_scope=*/1);
11664 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
11665 complain, in_decl);
11667 if (ctx == error_mark_node || f == error_mark_node)
11668 return error_mark_node;
11670 if (!MAYBE_CLASS_TYPE_P (ctx))
11672 if (complain & tf_error)
11673 error ("%qT is not a class, struct, or union type", ctx);
11674 return error_mark_node;
11676 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
11678 /* Normally, make_typename_type does not require that the CTX
11679 have complete type in order to allow things like:
11681 template <class T> struct S { typename S<T>::X Y; };
11683 But, such constructs have already been resolved by this
11684 point, so here CTX really should have complete type, unless
11685 it's a partial instantiation. */
11686 ctx = complete_type (ctx);
11687 if (!COMPLETE_TYPE_P (ctx))
11689 if (complain & tf_error)
11690 cxx_incomplete_type_error (NULL_TREE, ctx);
11691 return error_mark_node;
11695 f = make_typename_type (ctx, f, typename_type,
11696 (complain & tf_error) | tf_keep_type_decl);
11697 if (f == error_mark_node)
11699 if (TREE_CODE (f) == TYPE_DECL)
11701 complain |= tf_ignore_bad_quals;
11705 if (TREE_CODE (f) != TYPENAME_TYPE)
11707 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
11709 if (complain & tf_error)
11710 error ("%qT resolves to %qT, which is not an enumeration type",
11713 return error_mark_node;
11715 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
11717 if (complain & tf_error)
11718 error ("%qT resolves to %qT, which is is not a class type",
11721 return error_mark_node;
11725 return cp_build_qualified_type_real
11726 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11729 case UNBOUND_CLASS_TEMPLATE:
11731 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11732 in_decl, /*entering_scope=*/1);
11733 tree name = TYPE_IDENTIFIER (t);
11734 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11736 if (ctx == error_mark_node || name == error_mark_node)
11737 return error_mark_node;
11740 parm_list = tsubst_template_parms (parm_list, args, complain);
11741 return make_unbound_class_template (ctx, name, parm_list, complain);
11748 ++cp_unevaluated_operand;
11749 ++c_inhibit_evaluation_warnings;
11751 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11753 /*integral_constant_expression_p=*/false);
11755 --cp_unevaluated_operand;
11756 --c_inhibit_evaluation_warnings;
11758 type = finish_typeof (type);
11759 return cp_build_qualified_type_real (type,
11761 | cp_type_quals (type),
11765 case DECLTYPE_TYPE:
11769 ++cp_unevaluated_operand;
11770 ++c_inhibit_evaluation_warnings;
11772 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11774 /*integral_constant_expression_p=*/false);
11776 --cp_unevaluated_operand;
11777 --c_inhibit_evaluation_warnings;
11779 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11780 type = lambda_capture_field_type (type);
11781 else if (DECLTYPE_FOR_LAMBDA_PROXY (t))
11782 type = lambda_proxy_type (type);
11784 type = finish_decltype_type
11785 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11786 return cp_build_qualified_type_real (type,
11788 | cp_type_quals (type),
11792 case UNDERLYING_TYPE:
11794 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11795 complain, in_decl);
11796 return finish_underlying_type (type);
11799 case TYPE_ARGUMENT_PACK:
11800 case NONTYPE_ARGUMENT_PACK:
11802 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11804 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11808 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11810 /* For template nontype argument packs, also substitute into
11812 if (code == NONTYPE_ARGUMENT_PACK)
11813 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11831 /* We should use one of the expression tsubsts for these codes. */
11832 gcc_unreachable ();
11835 sorry ("use of %qs in template", tree_code_name [(int) code]);
11836 return error_mark_node;
11840 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11841 type of the expression on the left-hand side of the "." or "->"
11845 tsubst_baselink (tree baselink, tree object_type,
11846 tree args, tsubst_flags_t complain, tree in_decl)
11849 tree qualifying_scope;
11852 tree template_args = 0;
11853 bool template_id_p = false;
11855 /* A baselink indicates a function from a base class. Both the
11856 BASELINK_ACCESS_BINFO and the base class referenced may
11857 indicate bases of the template class, rather than the
11858 instantiated class. In addition, lookups that were not
11859 ambiguous before may be ambiguous now. Therefore, we perform
11860 the lookup again. */
11861 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11862 qualifying_scope = tsubst (qualifying_scope, args,
11863 complain, in_decl);
11864 fns = BASELINK_FUNCTIONS (baselink);
11865 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11866 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11868 template_id_p = true;
11869 template_args = TREE_OPERAND (fns, 1);
11870 fns = TREE_OPERAND (fns, 0);
11872 template_args = tsubst_template_args (template_args, args,
11873 complain, in_decl);
11875 name = DECL_NAME (get_first_fn (fns));
11876 if (IDENTIFIER_TYPENAME_P (name))
11877 name = mangle_conv_op_name_for_type (optype);
11878 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11880 return error_mark_node;
11882 /* If lookup found a single function, mark it as used at this
11883 point. (If it lookup found multiple functions the one selected
11884 later by overload resolution will be marked as used at that
11886 if (BASELINK_P (baselink))
11887 fns = BASELINK_FUNCTIONS (baselink);
11888 if (!template_id_p && !really_overloaded_fn (fns))
11889 mark_used (OVL_CURRENT (fns));
11891 /* Add back the template arguments, if present. */
11892 if (BASELINK_P (baselink) && template_id_p)
11893 BASELINK_FUNCTIONS (baselink)
11894 = build_nt (TEMPLATE_ID_EXPR,
11895 BASELINK_FUNCTIONS (baselink),
11897 /* Update the conversion operator type. */
11898 BASELINK_OPTYPE (baselink) = optype;
11901 object_type = current_class_type;
11902 return adjust_result_of_qualified_name_lookup (baselink,
11907 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11908 true if the qualified-id will be a postfix-expression in-and-of
11909 itself; false if more of the postfix-expression follows the
11910 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11914 tsubst_qualified_id (tree qualified_id, tree args,
11915 tsubst_flags_t complain, tree in_decl,
11916 bool done, bool address_p)
11922 tree template_args;
11924 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11926 /* Figure out what name to look up. */
11927 name = TREE_OPERAND (qualified_id, 1);
11928 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11930 is_template = true;
11931 template_args = TREE_OPERAND (name, 1);
11933 template_args = tsubst_template_args (template_args, args,
11934 complain, in_decl);
11935 name = TREE_OPERAND (name, 0);
11939 is_template = false;
11940 template_args = NULL_TREE;
11943 /* Substitute into the qualifying scope. When there are no ARGS, we
11944 are just trying to simplify a non-dependent expression. In that
11945 case the qualifying scope may be dependent, and, in any case,
11946 substituting will not help. */
11947 scope = TREE_OPERAND (qualified_id, 0);
11950 scope = tsubst (scope, args, complain, in_decl);
11951 expr = tsubst_copy (name, args, complain, in_decl);
11956 if (dependent_scope_p (scope))
11959 expr = build_min_nt (TEMPLATE_ID_EXPR, expr, template_args);
11960 return build_qualified_name (NULL_TREE, scope, expr,
11961 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11964 if (!BASELINK_P (name) && !DECL_P (expr))
11966 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11968 /* A BIT_NOT_EXPR is used to represent a destructor. */
11969 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11971 error ("qualifying type %qT does not match destructor name ~%qT",
11972 scope, TREE_OPERAND (expr, 0));
11973 expr = error_mark_node;
11976 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11977 /*is_type_p=*/0, false);
11980 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11981 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11982 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11984 if (complain & tf_error)
11986 error ("dependent-name %qE is parsed as a non-type, but "
11987 "instantiation yields a type", qualified_id);
11988 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11990 return error_mark_node;
11996 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11998 /* Remember that there was a reference to this entity. */
12002 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
12004 if (complain & tf_error)
12005 qualified_name_lookup_error (scope,
12006 TREE_OPERAND (qualified_id, 1),
12007 expr, input_location);
12008 return error_mark_node;
12012 expr = lookup_template_function (expr, template_args);
12014 if (expr == error_mark_node && complain & tf_error)
12015 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
12016 expr, input_location);
12017 else if (TYPE_P (scope))
12019 expr = (adjust_result_of_qualified_name_lookup
12020 (expr, scope, current_class_type));
12021 expr = (finish_qualified_id_expr
12022 (scope, expr, done, address_p && PTRMEM_OK_P (qualified_id),
12023 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
12024 /*template_arg_p=*/false));
12027 /* Expressions do not generally have reference type. */
12028 if (TREE_CODE (expr) != SCOPE_REF
12029 /* However, if we're about to form a pointer-to-member, we just
12030 want the referenced member referenced. */
12031 && TREE_CODE (expr) != OFFSET_REF)
12032 expr = convert_from_reference (expr);
12037 /* Like tsubst, but deals with expressions. This function just replaces
12038 template parms; to finish processing the resultant expression, use
12039 tsubst_copy_and_build or tsubst_expr. */
12042 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
12044 enum tree_code code;
12047 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
12050 code = TREE_CODE (t);
12055 r = retrieve_local_specialization (t);
12061 /* We get here for a use of 'this' in an NSDMI. */
12062 if (DECL_NAME (t) == this_identifier
12063 && at_function_scope_p ()
12064 && DECL_CONSTRUCTOR_P (current_function_decl))
12065 return current_class_ptr;
12067 /* This can happen for a parameter name used later in a function
12068 declaration (such as in a late-specified return type). Just
12069 make a dummy decl, since it's only used for its type. */
12070 gcc_assert (cp_unevaluated_operand != 0);
12071 /* We copy T because want to tsubst the PARM_DECL only,
12072 not the following PARM_DECLs that are chained to T. */
12074 r = tsubst_decl (c, args, complain);
12075 /* Give it the template pattern as its context; its true context
12076 hasn't been instantiated yet and this is good enough for
12078 DECL_CONTEXT (r) = DECL_CONTEXT (t);
12081 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
12082 r = ARGUMENT_PACK_SELECT_ARG (r);
12091 if (DECL_TEMPLATE_PARM_P (t))
12092 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
12093 /* There is no need to substitute into namespace-scope
12095 if (DECL_NAMESPACE_SCOPE_P (t))
12097 /* If ARGS is NULL, then T is known to be non-dependent. */
12098 if (args == NULL_TREE)
12099 return integral_constant_value (t);
12101 /* Unfortunately, we cannot just call lookup_name here.
12104 template <int I> int f() {
12106 struct S { void g() { E e = a; } };
12109 When we instantiate f<7>::S::g(), say, lookup_name is not
12110 clever enough to find f<7>::a. */
12112 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
12113 /*entering_scope=*/0);
12115 for (v = TYPE_VALUES (enum_type);
12117 v = TREE_CHAIN (v))
12118 if (TREE_PURPOSE (v) == DECL_NAME (t))
12119 return TREE_VALUE (v);
12121 /* We didn't find the name. That should never happen; if
12122 name-lookup found it during preliminary parsing, we
12123 should find it again here during instantiation. */
12124 gcc_unreachable ();
12129 if (DECL_CONTEXT (t))
12133 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
12134 /*entering_scope=*/1);
12135 if (ctx != DECL_CONTEXT (t))
12137 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
12140 if (complain & tf_error)
12141 error ("using invalid field %qD", t);
12142 return error_mark_node;
12151 case FUNCTION_DECL:
12152 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
12153 || local_variable_p (t))
12154 t = tsubst (t, args, complain, in_decl);
12158 case NAMESPACE_DECL:
12162 /* An OVERLOAD will always be a non-dependent overload set; an
12163 overload set from function scope will just be represented with an
12164 IDENTIFIER_NODE, and from class scope with a BASELINK. */
12165 gcc_assert (!uses_template_parms (t));
12169 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
12171 case TEMPLATE_DECL:
12172 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
12173 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
12174 args, complain, in_decl);
12175 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
12176 return tsubst (t, args, complain, in_decl);
12177 else if (DECL_CLASS_SCOPE_P (t)
12178 && uses_template_parms (DECL_CONTEXT (t)))
12180 /* Template template argument like the following example need
12183 template <template <class> class TT> struct C {};
12184 template <class T> struct D {
12185 template <class U> struct E {};
12190 We are processing the template argument `E' in #1 for
12191 the template instantiation #2. Originally, `E' is a
12192 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
12193 have to substitute this with one having context `D<int>'. */
12195 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
12196 return lookup_field (context, DECL_NAME(t), 0, false);
12199 /* Ordinary template template argument. */
12203 case REINTERPRET_CAST_EXPR:
12204 case CONST_CAST_EXPR:
12205 case STATIC_CAST_EXPR:
12206 case DYNAMIC_CAST_EXPR:
12207 case IMPLICIT_CONV_EXPR:
12211 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12212 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12215 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12221 ++cp_unevaluated_operand;
12222 ++c_inhibit_evaluation_warnings;
12223 /* We only want to compute the number of arguments. */
12224 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
12225 complain, in_decl);
12226 --cp_unevaluated_operand;
12227 --c_inhibit_evaluation_warnings;
12229 if (TREE_CODE (expanded) == TREE_VEC)
12230 len = TREE_VEC_LENGTH (expanded);
12232 if (expanded == error_mark_node)
12233 return error_mark_node;
12234 else if (PACK_EXPANSION_P (expanded)
12235 || (TREE_CODE (expanded) == TREE_VEC
12237 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
12239 if (TREE_CODE (expanded) == TREE_VEC)
12240 expanded = TREE_VEC_ELT (expanded, len - 1);
12242 if (TYPE_P (expanded))
12243 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
12244 complain & tf_error);
12246 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
12247 complain & tf_error);
12250 return build_int_cst (size_type_node, len);
12256 case TRUTH_NOT_EXPR:
12259 case UNARY_PLUS_EXPR: /* Unary + */
12261 case AT_ENCODE_EXPR:
12265 case REALPART_EXPR:
12266 case IMAGPART_EXPR:
12268 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12269 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12271 case COMPONENT_REF:
12276 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
12277 name = TREE_OPERAND (t, 1);
12278 if (TREE_CODE (name) == BIT_NOT_EXPR)
12280 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12281 complain, in_decl);
12282 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12284 else if (TREE_CODE (name) == SCOPE_REF
12285 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
12287 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
12288 complain, in_decl);
12289 name = TREE_OPERAND (name, 1);
12290 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12291 complain, in_decl);
12292 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12293 name = build_qualified_name (/*type=*/NULL_TREE,
12295 /*template_p=*/false);
12297 else if (BASELINK_P (name))
12298 name = tsubst_baselink (name,
12299 non_reference (TREE_TYPE (object)),
12303 name = tsubst_copy (name, args, complain, in_decl);
12304 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
12310 case TRUNC_DIV_EXPR:
12311 case CEIL_DIV_EXPR:
12312 case FLOOR_DIV_EXPR:
12313 case ROUND_DIV_EXPR:
12314 case EXACT_DIV_EXPR:
12318 case TRUNC_MOD_EXPR:
12319 case FLOOR_MOD_EXPR:
12320 case TRUTH_ANDIF_EXPR:
12321 case TRUTH_ORIF_EXPR:
12322 case TRUTH_AND_EXPR:
12323 case TRUTH_OR_EXPR:
12336 case COMPOUND_EXPR:
12339 case PREDECREMENT_EXPR:
12340 case PREINCREMENT_EXPR:
12341 case POSTDECREMENT_EXPR:
12342 case POSTINCREMENT_EXPR:
12344 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12345 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12348 return build_qualified_name (/*type=*/NULL_TREE,
12349 tsubst_copy (TREE_OPERAND (t, 0),
12350 args, complain, in_decl),
12351 tsubst_copy (TREE_OPERAND (t, 1),
12352 args, complain, in_decl),
12353 QUALIFIED_NAME_IS_TEMPLATE (t));
12358 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12359 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12360 NULL_TREE, NULL_TREE);
12364 int n = VL_EXP_OPERAND_LENGTH (t);
12365 tree result = build_vl_exp (CALL_EXPR, n);
12367 for (i = 0; i < n; i++)
12368 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
12369 complain, in_decl);
12375 case PSEUDO_DTOR_EXPR:
12378 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12379 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12380 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12381 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12388 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12389 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12390 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12391 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
12398 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12399 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12400 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
12401 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
12405 case TEMPLATE_ID_EXPR:
12407 /* Substituted template arguments */
12408 tree fn = TREE_OPERAND (t, 0);
12409 tree targs = TREE_OPERAND (t, 1);
12411 fn = tsubst_copy (fn, args, complain, in_decl);
12413 targs = tsubst_template_args (targs, args, complain, in_decl);
12415 return lookup_template_function (fn, targs);
12420 tree purpose, value, chain;
12422 if (t == void_list_node)
12425 purpose = TREE_PURPOSE (t);
12427 purpose = tsubst_copy (purpose, args, complain, in_decl);
12428 value = TREE_VALUE (t);
12430 value = tsubst_copy (value, args, complain, in_decl);
12431 chain = TREE_CHAIN (t);
12432 if (chain && chain != void_type_node)
12433 chain = tsubst_copy (chain, args, complain, in_decl);
12434 if (purpose == TREE_PURPOSE (t)
12435 && value == TREE_VALUE (t)
12436 && chain == TREE_CHAIN (t))
12438 return tree_cons (purpose, value, chain);
12443 case ENUMERAL_TYPE:
12445 case TEMPLATE_TYPE_PARM:
12446 case TEMPLATE_TEMPLATE_PARM:
12447 case BOUND_TEMPLATE_TEMPLATE_PARM:
12448 case TEMPLATE_PARM_INDEX:
12450 case REFERENCE_TYPE:
12452 case FUNCTION_TYPE:
12455 case TYPENAME_TYPE:
12456 case UNBOUND_CLASS_TEMPLATE:
12458 case DECLTYPE_TYPE:
12460 return tsubst (t, args, complain, in_decl);
12462 case IDENTIFIER_NODE:
12463 if (IDENTIFIER_TYPENAME_P (t))
12465 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12466 return mangle_conv_op_name_for_type (new_type);
12472 /* This is handled by tsubst_copy_and_build. */
12473 gcc_unreachable ();
12476 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
12478 tsubst (TREE_TYPE (t), args, complain, in_decl));
12480 case CLEANUP_POINT_EXPR:
12481 /* We shouldn't have built any of these during initial template
12482 generation. Instead, they should be built during instantiation
12483 in response to the saved STMT_IS_FULL_EXPR_P setting. */
12484 gcc_unreachable ();
12488 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12489 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12490 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12491 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
12492 mark_used (TREE_OPERAND (r, 1));
12495 case EXPR_PACK_EXPANSION:
12496 error ("invalid use of pack expansion expression");
12497 return error_mark_node;
12499 case NONTYPE_ARGUMENT_PACK:
12500 error ("use %<...%> to expand argument pack");
12501 return error_mark_node;
12508 /* Instantiate any typedefs in the type. */
12509 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12510 r = fold_convert (type, t);
12511 gcc_assert (TREE_CODE (r) == code);
12516 /* These can sometimes show up in a partial instantiation, but never
12517 involve template parms. */
12518 gcc_assert (!uses_template_parms (t));
12522 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
12523 gcc_checking_assert (false);
12528 /* Like tsubst_copy, but specifically for OpenMP clauses. */
12531 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
12534 tree new_clauses = NULL, nc, oc;
12536 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
12538 nc = copy_node (oc);
12539 OMP_CLAUSE_CHAIN (nc) = new_clauses;
12542 switch (OMP_CLAUSE_CODE (nc))
12544 case OMP_CLAUSE_LASTPRIVATE:
12545 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
12547 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
12548 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
12549 in_decl, /*integral_constant_expression_p=*/false);
12550 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
12551 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
12554 case OMP_CLAUSE_PRIVATE:
12555 case OMP_CLAUSE_SHARED:
12556 case OMP_CLAUSE_FIRSTPRIVATE:
12557 case OMP_CLAUSE_REDUCTION:
12558 case OMP_CLAUSE_COPYIN:
12559 case OMP_CLAUSE_COPYPRIVATE:
12560 case OMP_CLAUSE_IF:
12561 case OMP_CLAUSE_NUM_THREADS:
12562 case OMP_CLAUSE_SCHEDULE:
12563 case OMP_CLAUSE_COLLAPSE:
12564 case OMP_CLAUSE_FINAL:
12565 OMP_CLAUSE_OPERAND (nc, 0)
12566 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
12567 in_decl, /*integral_constant_expression_p=*/false);
12569 case OMP_CLAUSE_NOWAIT:
12570 case OMP_CLAUSE_ORDERED:
12571 case OMP_CLAUSE_DEFAULT:
12572 case OMP_CLAUSE_UNTIED:
12573 case OMP_CLAUSE_MERGEABLE:
12576 gcc_unreachable ();
12580 return finish_omp_clauses (nreverse (new_clauses));
12583 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
12586 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
12589 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
12591 tree purpose, value, chain;
12596 if (TREE_CODE (t) != TREE_LIST)
12597 return tsubst_copy_and_build (t, args, complain, in_decl,
12598 /*function_p=*/false,
12599 /*integral_constant_expression_p=*/false);
12601 if (t == void_list_node)
12604 purpose = TREE_PURPOSE (t);
12606 purpose = RECUR (purpose);
12607 value = TREE_VALUE (t);
12608 if (value && TREE_CODE (value) != LABEL_DECL)
12609 value = RECUR (value);
12610 chain = TREE_CHAIN (t);
12611 if (chain && chain != void_type_node)
12612 chain = RECUR (chain);
12613 return tree_cons (purpose, value, chain);
12617 /* Substitute one OMP_FOR iterator. */
12620 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
12621 tree condv, tree incrv, tree *clauses,
12622 tree args, tsubst_flags_t complain, tree in_decl,
12623 bool integral_constant_expression_p)
12625 #define RECUR(NODE) \
12626 tsubst_expr ((NODE), args, complain, in_decl, \
12627 integral_constant_expression_p)
12628 tree decl, init, cond, incr, auto_node;
12630 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
12631 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
12632 decl = RECUR (TREE_OPERAND (init, 0));
12633 init = TREE_OPERAND (init, 1);
12634 auto_node = type_uses_auto (TREE_TYPE (decl));
12635 if (auto_node && init)
12637 tree init_expr = init;
12638 if (TREE_CODE (init_expr) == DECL_EXPR)
12639 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
12640 init_expr = RECUR (init_expr);
12642 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
12644 gcc_assert (!type_dependent_expression_p (decl));
12646 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
12648 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
12649 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12650 if (TREE_CODE (incr) == MODIFY_EXPR)
12651 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
12652 RECUR (TREE_OPERAND (incr, 1)),
12655 incr = RECUR (incr);
12656 TREE_VEC_ELT (declv, i) = decl;
12657 TREE_VEC_ELT (initv, i) = init;
12658 TREE_VEC_ELT (condv, i) = cond;
12659 TREE_VEC_ELT (incrv, i) = incr;
12663 if (init && TREE_CODE (init) != DECL_EXPR)
12666 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
12668 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
12669 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
12670 && OMP_CLAUSE_DECL (c) == decl)
12672 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
12673 && OMP_CLAUSE_DECL (c) == decl)
12674 error ("iteration variable %qD should not be firstprivate", decl);
12675 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
12676 && OMP_CLAUSE_DECL (c) == decl)
12677 error ("iteration variable %qD should not be reduction", decl);
12681 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
12682 OMP_CLAUSE_DECL (c) = decl;
12683 c = finish_omp_clauses (c);
12686 OMP_CLAUSE_CHAIN (c) = *clauses;
12691 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
12692 if (COMPARISON_CLASS_P (cond))
12693 cond = build2 (TREE_CODE (cond), boolean_type_node,
12694 RECUR (TREE_OPERAND (cond, 0)),
12695 RECUR (TREE_OPERAND (cond, 1)));
12697 cond = RECUR (cond);
12698 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12699 switch (TREE_CODE (incr))
12701 case PREINCREMENT_EXPR:
12702 case PREDECREMENT_EXPR:
12703 case POSTINCREMENT_EXPR:
12704 case POSTDECREMENT_EXPR:
12705 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
12706 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
12709 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12710 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12712 tree rhs = TREE_OPERAND (incr, 1);
12713 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12714 RECUR (TREE_OPERAND (incr, 0)),
12715 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12716 RECUR (TREE_OPERAND (rhs, 0)),
12717 RECUR (TREE_OPERAND (rhs, 1))));
12720 incr = RECUR (incr);
12723 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12724 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12726 tree lhs = RECUR (TREE_OPERAND (incr, 0));
12727 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
12728 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
12729 TREE_TYPE (decl), lhs,
12730 RECUR (TREE_OPERAND (incr, 2))));
12732 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
12733 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
12734 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
12736 tree rhs = TREE_OPERAND (incr, 2);
12737 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12738 RECUR (TREE_OPERAND (incr, 0)),
12739 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12740 RECUR (TREE_OPERAND (rhs, 0)),
12741 RECUR (TREE_OPERAND (rhs, 1))));
12744 incr = RECUR (incr);
12747 incr = RECUR (incr);
12751 TREE_VEC_ELT (declv, i) = decl;
12752 TREE_VEC_ELT (initv, i) = init;
12753 TREE_VEC_ELT (condv, i) = cond;
12754 TREE_VEC_ELT (incrv, i) = incr;
12758 /* Like tsubst_copy for expressions, etc. but also does semantic
12762 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12763 bool integral_constant_expression_p)
12765 #define RECUR(NODE) \
12766 tsubst_expr ((NODE), args, complain, in_decl, \
12767 integral_constant_expression_p)
12771 if (t == NULL_TREE || t == error_mark_node)
12774 if (EXPR_HAS_LOCATION (t))
12775 input_location = EXPR_LOCATION (t);
12776 if (STATEMENT_CODE_P (TREE_CODE (t)))
12777 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12779 switch (TREE_CODE (t))
12781 case STATEMENT_LIST:
12783 tree_stmt_iterator i;
12784 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12785 RECUR (tsi_stmt (i));
12789 case CTOR_INITIALIZER:
12790 finish_mem_initializers (tsubst_initializer_list
12791 (TREE_OPERAND (t, 0), args));
12795 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12799 tmp = RECUR (EXPR_STMT_EXPR (t));
12800 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12801 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12803 finish_expr_stmt (tmp);
12807 do_using_directive (USING_STMT_NAMESPACE (t));
12812 tree decl, pattern_decl;
12815 pattern_decl = decl = DECL_EXPR_DECL (t);
12816 if (TREE_CODE (decl) == LABEL_DECL)
12817 finish_label_decl (DECL_NAME (decl));
12818 else if (TREE_CODE (decl) == USING_DECL)
12820 tree scope = USING_DECL_SCOPE (decl);
12821 tree name = DECL_NAME (decl);
12824 scope = tsubst (scope, args, complain, in_decl);
12825 decl = lookup_qualified_name (scope, name,
12826 /*is_type_p=*/false,
12827 /*complain=*/false);
12828 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12829 qualified_name_lookup_error (scope, name, decl, input_location);
12831 do_local_using_decl (decl, scope, name);
12835 init = DECL_INITIAL (decl);
12836 decl = tsubst (decl, args, complain, in_decl);
12837 if (decl != error_mark_node)
12839 /* By marking the declaration as instantiated, we avoid
12840 trying to instantiate it. Since instantiate_decl can't
12841 handle local variables, and since we've already done
12842 all that needs to be done, that's the right thing to
12844 if (TREE_CODE (decl) == VAR_DECL)
12845 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12846 if (TREE_CODE (decl) == VAR_DECL
12847 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12848 /* Anonymous aggregates are a special case. */
12849 finish_anon_union (decl);
12850 else if (is_capture_proxy (DECL_EXPR_DECL (t)))
12852 DECL_CONTEXT (decl) = current_function_decl;
12853 insert_capture_proxy (decl);
12857 int const_init = false;
12858 maybe_push_decl (decl);
12859 if (TREE_CODE (decl) == VAR_DECL
12860 && DECL_PRETTY_FUNCTION_P (decl))
12862 /* For __PRETTY_FUNCTION__ we have to adjust the
12864 const char *const name
12865 = cxx_printable_name (current_function_decl, 2);
12866 init = cp_fname_init (name, &TREE_TYPE (decl));
12870 tree t = RECUR (init);
12874 /* If we had an initializer but it
12875 instantiated to nothing,
12876 value-initialize the object. This will
12877 only occur when the initializer was a
12878 pack expansion where the parameter packs
12879 used in that expansion were of length
12881 init = build_value_init (TREE_TYPE (decl),
12883 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12884 init = get_target_expr_sfinae (init, complain);
12890 if (TREE_CODE (decl) == VAR_DECL)
12891 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12893 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12898 /* A DECL_EXPR can also be used as an expression, in the condition
12899 clause of an if/for/while construct. */
12904 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12905 RECUR (FOR_INIT_STMT (t));
12906 finish_for_init_stmt (stmt);
12907 tmp = RECUR (FOR_COND (t));
12908 finish_for_cond (tmp, stmt);
12909 tmp = RECUR (FOR_EXPR (t));
12910 finish_for_expr (tmp, stmt);
12911 RECUR (FOR_BODY (t));
12912 finish_for_stmt (stmt);
12915 case RANGE_FOR_STMT:
12918 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12919 decl = RANGE_FOR_DECL (t);
12920 decl = tsubst (decl, args, complain, in_decl);
12921 maybe_push_decl (decl);
12922 expr = RECUR (RANGE_FOR_EXPR (t));
12923 stmt = cp_convert_range_for (stmt, decl, expr);
12924 RECUR (RANGE_FOR_BODY (t));
12925 finish_for_stmt (stmt);
12930 stmt = begin_while_stmt ();
12931 tmp = RECUR (WHILE_COND (t));
12932 finish_while_stmt_cond (tmp, stmt);
12933 RECUR (WHILE_BODY (t));
12934 finish_while_stmt (stmt);
12938 stmt = begin_do_stmt ();
12939 RECUR (DO_BODY (t));
12940 finish_do_body (stmt);
12941 tmp = RECUR (DO_COND (t));
12942 finish_do_stmt (tmp, stmt);
12946 stmt = begin_if_stmt ();
12947 tmp = RECUR (IF_COND (t));
12948 finish_if_stmt_cond (tmp, stmt);
12949 RECUR (THEN_CLAUSE (t));
12950 finish_then_clause (stmt);
12952 if (ELSE_CLAUSE (t))
12954 begin_else_clause (stmt);
12955 RECUR (ELSE_CLAUSE (t));
12956 finish_else_clause (stmt);
12959 finish_if_stmt (stmt);
12963 if (BIND_EXPR_BODY_BLOCK (t))
12964 stmt = begin_function_body ();
12966 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12967 ? BCS_TRY_BLOCK : 0);
12969 RECUR (BIND_EXPR_BODY (t));
12971 if (BIND_EXPR_BODY_BLOCK (t))
12972 finish_function_body (stmt);
12974 finish_compound_stmt (stmt);
12978 finish_break_stmt ();
12981 case CONTINUE_STMT:
12982 finish_continue_stmt ();
12986 stmt = begin_switch_stmt ();
12987 tmp = RECUR (SWITCH_STMT_COND (t));
12988 finish_switch_cond (tmp, stmt);
12989 RECUR (SWITCH_STMT_BODY (t));
12990 finish_switch_stmt (stmt);
12993 case CASE_LABEL_EXPR:
12994 finish_case_label (EXPR_LOCATION (t),
12995 RECUR (CASE_LOW (t)),
12996 RECUR (CASE_HIGH (t)));
13001 tree decl = LABEL_EXPR_LABEL (t);
13004 label = finish_label_stmt (DECL_NAME (decl));
13005 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
13006 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
13011 tmp = GOTO_DESTINATION (t);
13012 if (TREE_CODE (tmp) != LABEL_DECL)
13013 /* Computed goto's must be tsubst'd into. On the other hand,
13014 non-computed gotos must not be; the identifier in question
13015 will have no binding. */
13018 tmp = DECL_NAME (tmp);
13019 finish_goto_stmt (tmp);
13023 tmp = finish_asm_stmt
13024 (ASM_VOLATILE_P (t),
13025 RECUR (ASM_STRING (t)),
13026 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
13027 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
13028 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
13029 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
13031 tree asm_expr = tmp;
13032 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
13033 asm_expr = TREE_OPERAND (asm_expr, 0);
13034 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
13041 stmt = begin_try_block ();
13042 RECUR (TRY_STMTS (t));
13043 finish_cleanup_try_block (stmt);
13044 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
13048 tree compound_stmt = NULL_TREE;
13050 if (FN_TRY_BLOCK_P (t))
13051 stmt = begin_function_try_block (&compound_stmt);
13053 stmt = begin_try_block ();
13055 RECUR (TRY_STMTS (t));
13057 if (FN_TRY_BLOCK_P (t))
13058 finish_function_try_block (stmt);
13060 finish_try_block (stmt);
13062 RECUR (TRY_HANDLERS (t));
13063 if (FN_TRY_BLOCK_P (t))
13064 finish_function_handler_sequence (stmt, compound_stmt);
13066 finish_handler_sequence (stmt);
13072 tree decl = HANDLER_PARMS (t);
13076 decl = tsubst (decl, args, complain, in_decl);
13077 /* Prevent instantiate_decl from trying to instantiate
13078 this variable. We've already done all that needs to be
13080 if (decl != error_mark_node)
13081 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
13083 stmt = begin_handler ();
13084 finish_handler_parms (decl, stmt);
13085 RECUR (HANDLER_BODY (t));
13086 finish_handler (stmt);
13091 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13094 case STATIC_ASSERT:
13097 tsubst_expr (STATIC_ASSERT_CONDITION (t),
13100 /*integral_constant_expression_p=*/true);
13101 finish_static_assert (condition,
13102 STATIC_ASSERT_MESSAGE (t),
13103 STATIC_ASSERT_SOURCE_LOCATION (t),
13104 /*member_p=*/false);
13109 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
13110 args, complain, in_decl);
13111 stmt = begin_omp_parallel ();
13112 RECUR (OMP_PARALLEL_BODY (t));
13113 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
13114 = OMP_PARALLEL_COMBINED (t);
13118 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
13119 args, complain, in_decl);
13120 stmt = begin_omp_task ();
13121 RECUR (OMP_TASK_BODY (t));
13122 finish_omp_task (tmp, stmt);
13127 tree clauses, body, pre_body;
13128 tree declv, initv, condv, incrv;
13131 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
13132 args, complain, in_decl);
13133 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13134 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13135 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13136 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13138 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
13139 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
13140 &clauses, args, complain, in_decl,
13141 integral_constant_expression_p);
13143 stmt = begin_omp_structured_block ();
13145 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
13146 if (TREE_VEC_ELT (initv, i) == NULL
13147 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
13148 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
13149 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
13151 tree init = RECUR (TREE_VEC_ELT (initv, i));
13152 gcc_assert (init == TREE_VEC_ELT (declv, i));
13153 TREE_VEC_ELT (initv, i) = NULL_TREE;
13157 tree decl_expr = TREE_VEC_ELT (initv, i);
13158 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
13159 gcc_assert (init != NULL);
13160 TREE_VEC_ELT (initv, i) = RECUR (init);
13161 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
13163 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
13166 pre_body = push_stmt_list ();
13167 RECUR (OMP_FOR_PRE_BODY (t));
13168 pre_body = pop_stmt_list (pre_body);
13170 body = push_stmt_list ();
13171 RECUR (OMP_FOR_BODY (t));
13172 body = pop_stmt_list (body);
13174 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
13175 body, pre_body, clauses);
13177 add_stmt (finish_omp_structured_block (stmt));
13183 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
13184 stmt = push_stmt_list ();
13185 RECUR (OMP_BODY (t));
13186 stmt = pop_stmt_list (stmt);
13189 OMP_BODY (t) = stmt;
13190 OMP_CLAUSES (t) = tmp;
13198 stmt = push_stmt_list ();
13199 RECUR (OMP_BODY (t));
13200 stmt = pop_stmt_list (stmt);
13203 OMP_BODY (t) = stmt;
13208 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
13209 if (TREE_CODE (TREE_OPERAND (t, 1)) != MODIFY_EXPR)
13211 tree op1 = TREE_OPERAND (t, 1);
13212 tree rhs1 = NULL_TREE;
13214 if (TREE_CODE (op1) == COMPOUND_EXPR)
13216 rhs1 = RECUR (TREE_OPERAND (op1, 0));
13217 op1 = TREE_OPERAND (op1, 1);
13219 lhs = RECUR (TREE_OPERAND (op1, 0));
13220 rhs = RECUR (TREE_OPERAND (op1, 1));
13221 finish_omp_atomic (OMP_ATOMIC, TREE_CODE (op1), lhs, rhs,
13222 NULL_TREE, NULL_TREE, rhs1);
13226 tree op1 = TREE_OPERAND (t, 1);
13227 tree v = NULL_TREE, lhs, rhs = NULL_TREE, lhs1 = NULL_TREE;
13228 tree rhs1 = NULL_TREE;
13229 enum tree_code code = TREE_CODE (TREE_OPERAND (op1, 1));
13230 enum tree_code opcode = NOP_EXPR;
13231 if (code == OMP_ATOMIC_READ)
13233 v = RECUR (TREE_OPERAND (op1, 0));
13234 lhs = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13236 else if (code == OMP_ATOMIC_CAPTURE_OLD
13237 || code == OMP_ATOMIC_CAPTURE_NEW)
13239 tree op11 = TREE_OPERAND (TREE_OPERAND (op1, 1), 1);
13240 v = RECUR (TREE_OPERAND (op1, 0));
13241 lhs1 = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13242 if (TREE_CODE (op11) == COMPOUND_EXPR)
13244 rhs1 = RECUR (TREE_OPERAND (op11, 0));
13245 op11 = TREE_OPERAND (op11, 1);
13247 lhs = RECUR (TREE_OPERAND (op11, 0));
13248 rhs = RECUR (TREE_OPERAND (op11, 1));
13249 opcode = TREE_CODE (op11);
13254 lhs = RECUR (TREE_OPERAND (op1, 0));
13255 rhs = RECUR (TREE_OPERAND (op1, 1));
13257 finish_omp_atomic (code, opcode, lhs, rhs, v, lhs1, rhs1);
13261 case TRANSACTION_EXPR:
13264 flags |= (TRANSACTION_EXPR_OUTER (t) ? TM_STMT_ATTR_OUTER : 0);
13265 flags |= (TRANSACTION_EXPR_RELAXED (t) ? TM_STMT_ATTR_RELAXED : 0);
13267 if (TRANSACTION_EXPR_IS_STMT (t))
13269 tree body = TRANSACTION_EXPR_BODY (t);
13270 tree noex = NULL_TREE;
13271 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR)
13273 noex = MUST_NOT_THROW_COND (body);
13274 if (noex == NULL_TREE)
13275 noex = boolean_true_node;
13276 body = TREE_OPERAND (body, 0);
13278 stmt = begin_transaction_stmt (input_location, NULL, flags);
13280 finish_transaction_stmt (stmt, NULL, flags, RECUR (noex));
13284 stmt = build_transaction_expr (EXPR_LOCATION (t),
13285 RECUR (TRANSACTION_EXPR_BODY (t)),
13292 case MUST_NOT_THROW_EXPR:
13293 return build_must_not_throw_expr (RECUR (TREE_OPERAND (t, 0)),
13294 RECUR (MUST_NOT_THROW_COND (t)));
13296 case EXPR_PACK_EXPANSION:
13297 error ("invalid use of pack expansion expression");
13298 return error_mark_node;
13300 case NONTYPE_ARGUMENT_PACK:
13301 error ("use %<...%> to expand argument pack");
13302 return error_mark_node;
13305 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
13307 return tsubst_copy_and_build (t, args, complain, in_decl,
13308 /*function_p=*/false,
13309 integral_constant_expression_p);
13316 /* T is a postfix-expression that is not being used in a function
13317 call. Return the substituted version of T. */
13320 tsubst_non_call_postfix_expression (tree t, tree args,
13321 tsubst_flags_t complain,
13324 if (TREE_CODE (t) == SCOPE_REF)
13325 t = tsubst_qualified_id (t, args, complain, in_decl,
13326 /*done=*/false, /*address_p=*/false);
13328 t = tsubst_copy_and_build (t, args, complain, in_decl,
13329 /*function_p=*/false,
13330 /*integral_constant_expression_p=*/false);
13335 /* Like tsubst but deals with expressions and performs semantic
13336 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
13339 tsubst_copy_and_build (tree t,
13341 tsubst_flags_t complain,
13344 bool integral_constant_expression_p)
13346 #define RECUR(NODE) \
13347 tsubst_copy_and_build (NODE, args, complain, in_decl, \
13348 /*function_p=*/false, \
13349 integral_constant_expression_p)
13353 if (t == NULL_TREE || t == error_mark_node)
13356 switch (TREE_CODE (t))
13360 /* Fall through. */
13361 case IDENTIFIER_NODE:
13365 bool non_integral_constant_expression_p;
13366 const char *error_msg;
13368 if (IDENTIFIER_TYPENAME_P (t))
13370 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13371 t = mangle_conv_op_name_for_type (new_type);
13374 /* Look up the name. */
13375 decl = lookup_name (t);
13377 /* By convention, expressions use ERROR_MARK_NODE to indicate
13378 failure, not NULL_TREE. */
13379 if (decl == NULL_TREE)
13380 decl = error_mark_node;
13382 decl = finish_id_expression (t, decl, NULL_TREE,
13384 integral_constant_expression_p,
13385 /*allow_non_integral_constant_expression_p=*/(cxx_dialect >= cxx0x),
13386 &non_integral_constant_expression_p,
13387 /*template_p=*/false,
13389 /*address_p=*/false,
13390 /*template_arg_p=*/false,
13395 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
13397 if (complain & tf_error)
13398 unqualified_name_lookup_error (decl);
13399 decl = error_mark_node;
13404 case TEMPLATE_ID_EXPR:
13407 tree templ = RECUR (TREE_OPERAND (t, 0));
13408 tree targs = TREE_OPERAND (t, 1);
13411 targs = tsubst_template_args (targs, args, complain, in_decl);
13413 if (TREE_CODE (templ) == COMPONENT_REF)
13415 object = TREE_OPERAND (templ, 0);
13416 templ = TREE_OPERAND (templ, 1);
13419 object = NULL_TREE;
13420 templ = lookup_template_function (templ, targs);
13423 return build3 (COMPONENT_REF, TREE_TYPE (templ),
13424 object, templ, NULL_TREE);
13426 return baselink_for_fns (templ);
13431 tree r = RECUR (TREE_OPERAND (t, 0));
13433 if (REFERENCE_REF_P (t))
13435 /* A type conversion to reference type will be enclosed in
13436 such an indirect ref, but the substitution of the cast
13437 will have also added such an indirect ref. */
13438 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
13439 r = convert_from_reference (r);
13442 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
13448 (tsubst (TREE_TYPE (t), args, complain, in_decl),
13449 RECUR (TREE_OPERAND (t, 0)));
13451 case IMPLICIT_CONV_EXPR:
13453 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13454 tree expr = RECUR (TREE_OPERAND (t, 0));
13455 int flags = LOOKUP_IMPLICIT;
13456 if (IMPLICIT_CONV_EXPR_DIRECT_INIT (t))
13457 flags = LOOKUP_NORMAL;
13458 return perform_implicit_conversion_flags (type, expr, complain,
13465 tsubst (TREE_TYPE (t), args, complain, in_decl),
13466 RECUR (TREE_OPERAND (t, 0)));
13469 case REINTERPRET_CAST_EXPR:
13470 case CONST_CAST_EXPR:
13471 case DYNAMIC_CAST_EXPR:
13472 case STATIC_CAST_EXPR:
13477 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13478 if (integral_constant_expression_p
13479 && !cast_valid_in_integral_constant_expression_p (type))
13481 if (complain & tf_error)
13482 error ("a cast to a type other than an integral or "
13483 "enumeration type cannot appear in a constant-expression");
13484 return error_mark_node;
13487 op = RECUR (TREE_OPERAND (t, 0));
13489 switch (TREE_CODE (t))
13492 return build_functional_cast (type, op, complain);
13493 case REINTERPRET_CAST_EXPR:
13494 return build_reinterpret_cast (type, op, complain);
13495 case CONST_CAST_EXPR:
13496 return build_const_cast (type, op, complain);
13497 case DYNAMIC_CAST_EXPR:
13498 return build_dynamic_cast (type, op, complain);
13499 case STATIC_CAST_EXPR:
13500 return build_static_cast (type, op, complain);
13502 gcc_unreachable ();
13506 case POSTDECREMENT_EXPR:
13507 case POSTINCREMENT_EXPR:
13508 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13509 args, complain, in_decl);
13510 return build_x_unary_op (TREE_CODE (t), op1, complain);
13512 case PREDECREMENT_EXPR:
13513 case PREINCREMENT_EXPR:
13517 case TRUTH_NOT_EXPR:
13518 case UNARY_PLUS_EXPR: /* Unary + */
13519 case REALPART_EXPR:
13520 case IMAGPART_EXPR:
13521 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
13524 case FIX_TRUNC_EXPR:
13525 return cp_build_unary_op (FIX_TRUNC_EXPR, RECUR (TREE_OPERAND (t, 0)),
13529 op1 = TREE_OPERAND (t, 0);
13530 if (TREE_CODE (op1) == LABEL_DECL)
13531 return finish_label_address_expr (DECL_NAME (op1),
13532 EXPR_LOCATION (op1));
13533 if (TREE_CODE (op1) == SCOPE_REF)
13534 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
13535 /*done=*/true, /*address_p=*/true);
13537 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
13539 return build_x_unary_op (ADDR_EXPR, op1, complain);
13544 case TRUNC_DIV_EXPR:
13545 case CEIL_DIV_EXPR:
13546 case FLOOR_DIV_EXPR:
13547 case ROUND_DIV_EXPR:
13548 case EXACT_DIV_EXPR:
13552 case TRUNC_MOD_EXPR:
13553 case FLOOR_MOD_EXPR:
13554 case TRUTH_ANDIF_EXPR:
13555 case TRUTH_ORIF_EXPR:
13556 case TRUTH_AND_EXPR:
13557 case TRUTH_OR_EXPR:
13573 tree r = build_x_binary_op
13575 RECUR (TREE_OPERAND (t, 0)),
13576 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
13578 : TREE_CODE (TREE_OPERAND (t, 0))),
13579 RECUR (TREE_OPERAND (t, 1)),
13580 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
13582 : TREE_CODE (TREE_OPERAND (t, 1))),
13585 if (EXPR_P (r) && TREE_NO_WARNING (t))
13586 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13591 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
13592 /*address_p=*/false);
13594 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13595 args, complain, in_decl);
13596 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
13599 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
13600 return tsubst_copy (t, args, complain, in_decl);
13604 op1 = TREE_OPERAND (t, 0);
13607 /* When there are no ARGS, we are trying to evaluate a
13608 non-dependent expression from the parser. Trying to do
13609 the substitutions may not work. */
13611 op1 = TREE_TYPE (op1);
13615 ++cp_unevaluated_operand;
13616 ++c_inhibit_evaluation_warnings;
13617 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13618 /*function_p=*/false,
13619 /*integral_constant_expression_p=*/false);
13620 --cp_unevaluated_operand;
13621 --c_inhibit_evaluation_warnings;
13624 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
13625 complain & tf_error);
13627 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
13628 complain & tf_error);
13630 case AT_ENCODE_EXPR:
13632 op1 = TREE_OPERAND (t, 0);
13633 ++cp_unevaluated_operand;
13634 ++c_inhibit_evaluation_warnings;
13635 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13636 /*function_p=*/false,
13637 /*integral_constant_expression_p=*/false);
13638 --cp_unevaluated_operand;
13639 --c_inhibit_evaluation_warnings;
13640 return objc_build_encode_expr (op1);
13643 case NOEXCEPT_EXPR:
13644 op1 = TREE_OPERAND (t, 0);
13645 ++cp_unevaluated_operand;
13646 ++c_inhibit_evaluation_warnings;
13647 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13648 /*function_p=*/false,
13649 /*integral_constant_expression_p=*/false);
13650 --cp_unevaluated_operand;
13651 --c_inhibit_evaluation_warnings;
13652 return finish_noexcept_expr (op1, complain);
13656 tree r = build_x_modify_expr
13657 (RECUR (TREE_OPERAND (t, 0)),
13658 TREE_CODE (TREE_OPERAND (t, 1)),
13659 RECUR (TREE_OPERAND (t, 2)),
13661 /* TREE_NO_WARNING must be set if either the expression was
13662 parenthesized or it uses an operator such as >>= rather
13663 than plain assignment. In the former case, it was already
13664 set and must be copied. In the latter case,
13665 build_x_modify_expr sets it and it must not be reset
13667 if (TREE_NO_WARNING (t))
13668 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13673 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13674 args, complain, in_decl);
13675 /* Remember that there was a reference to this entity. */
13678 return build_x_arrow (op1);
13682 tree placement = RECUR (TREE_OPERAND (t, 0));
13683 tree init = RECUR (TREE_OPERAND (t, 3));
13684 VEC(tree,gc) *placement_vec;
13685 VEC(tree,gc) *init_vec;
13688 if (placement == NULL_TREE)
13689 placement_vec = NULL;
13692 placement_vec = make_tree_vector ();
13693 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
13694 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
13697 /* If there was an initializer in the original tree, but it
13698 instantiated to an empty list, then we should pass a
13699 non-NULL empty vector to tell build_new that it was an
13700 empty initializer() rather than no initializer. This can
13701 only happen when the initializer is a pack expansion whose
13702 parameter packs are of length zero. */
13703 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
13707 init_vec = make_tree_vector ();
13708 if (init == void_zero_node)
13709 gcc_assert (init_vec != NULL);
13712 for (; init != NULL_TREE; init = TREE_CHAIN (init))
13713 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
13717 ret = build_new (&placement_vec,
13718 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
13719 RECUR (TREE_OPERAND (t, 2)),
13721 NEW_EXPR_USE_GLOBAL (t),
13724 if (placement_vec != NULL)
13725 release_tree_vector (placement_vec);
13726 if (init_vec != NULL)
13727 release_tree_vector (init_vec);
13733 return delete_sanity
13734 (RECUR (TREE_OPERAND (t, 0)),
13735 RECUR (TREE_OPERAND (t, 1)),
13736 DELETE_EXPR_USE_VEC (t),
13737 DELETE_EXPR_USE_GLOBAL (t),
13740 case COMPOUND_EXPR:
13741 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
13742 RECUR (TREE_OPERAND (t, 1)),
13748 VEC(tree,gc) *call_args;
13749 unsigned int nargs, i;
13754 function = CALL_EXPR_FN (t);
13755 /* When we parsed the expression, we determined whether or
13756 not Koenig lookup should be performed. */
13757 koenig_p = KOENIG_LOOKUP_P (t);
13758 if (TREE_CODE (function) == SCOPE_REF)
13760 qualified_p = true;
13761 function = tsubst_qualified_id (function, args, complain, in_decl,
13763 /*address_p=*/false);
13765 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
13767 /* Do nothing; calling tsubst_copy_and_build on an identifier
13768 would incorrectly perform unqualified lookup again.
13770 Note that we can also have an IDENTIFIER_NODE if the earlier
13771 unqualified lookup found a member function; in that case
13772 koenig_p will be false and we do want to do the lookup
13773 again to find the instantiated member function.
13775 FIXME but doing that causes c++/15272, so we need to stop
13776 using IDENTIFIER_NODE in that situation. */
13777 qualified_p = false;
13781 if (TREE_CODE (function) == COMPONENT_REF)
13783 tree op = TREE_OPERAND (function, 1);
13785 qualified_p = (TREE_CODE (op) == SCOPE_REF
13786 || (BASELINK_P (op)
13787 && BASELINK_QUALIFIED_P (op)));
13790 qualified_p = false;
13792 function = tsubst_copy_and_build (function, args, complain,
13795 integral_constant_expression_p);
13797 if (BASELINK_P (function))
13798 qualified_p = true;
13801 nargs = call_expr_nargs (t);
13802 call_args = make_tree_vector ();
13803 for (i = 0; i < nargs; ++i)
13805 tree arg = CALL_EXPR_ARG (t, i);
13807 if (!PACK_EXPANSION_P (arg))
13808 VEC_safe_push (tree, gc, call_args,
13809 RECUR (CALL_EXPR_ARG (t, i)));
13812 /* Expand the pack expansion and push each entry onto
13814 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
13815 if (TREE_CODE (arg) == TREE_VEC)
13817 unsigned int len, j;
13819 len = TREE_VEC_LENGTH (arg);
13820 for (j = 0; j < len; ++j)
13822 tree value = TREE_VEC_ELT (arg, j);
13823 if (value != NULL_TREE)
13824 value = convert_from_reference (value);
13825 VEC_safe_push (tree, gc, call_args, value);
13830 /* A partial substitution. Add one entry. */
13831 VEC_safe_push (tree, gc, call_args, arg);
13836 /* We do not perform argument-dependent lookup if normal
13837 lookup finds a non-function, in accordance with the
13838 expected resolution of DR 218. */
13840 && ((is_overloaded_fn (function)
13841 /* If lookup found a member function, the Koenig lookup is
13842 not appropriate, even if an unqualified-name was used
13843 to denote the function. */
13844 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
13845 || TREE_CODE (function) == IDENTIFIER_NODE)
13846 /* Only do this when substitution turns a dependent call
13847 into a non-dependent call. */
13848 && type_dependent_expression_p_push (t)
13849 && !any_type_dependent_arguments_p (call_args))
13850 function = perform_koenig_lookup (function, call_args, false,
13853 if (TREE_CODE (function) == IDENTIFIER_NODE
13854 && !any_type_dependent_arguments_p (call_args))
13856 if (koenig_p && (complain & tf_warning_or_error))
13858 /* For backwards compatibility and good diagnostics, try
13859 the unqualified lookup again if we aren't in SFINAE
13861 tree unq = (tsubst_copy_and_build
13862 (function, args, complain, in_decl, true,
13863 integral_constant_expression_p));
13864 if (unq == error_mark_node)
13865 return error_mark_node;
13867 if (unq != function)
13870 if (TREE_CODE (fn) == INDIRECT_REF)
13871 fn = TREE_OPERAND (fn, 0);
13872 if (TREE_CODE (fn) == COMPONENT_REF)
13873 fn = TREE_OPERAND (fn, 1);
13874 if (is_overloaded_fn (fn))
13875 fn = get_first_fn (fn);
13876 permerror (EXPR_LOC_OR_HERE (t),
13877 "%qD was not declared in this scope, "
13878 "and no declarations were found by "
13879 "argument-dependent lookup at the point "
13880 "of instantiation", function);
13882 /* Can't say anything more. */;
13883 else if (DECL_CLASS_SCOPE_P (fn))
13885 inform (EXPR_LOC_OR_HERE (t),
13886 "declarations in dependent base %qT are "
13887 "not found by unqualified lookup",
13888 DECL_CLASS_CONTEXT (fn));
13889 if (current_class_ptr)
13890 inform (EXPR_LOC_OR_HERE (t),
13891 "use %<this->%D%> instead", function);
13893 inform (EXPR_LOC_OR_HERE (t),
13894 "use %<%T::%D%> instead",
13895 current_class_name, function);
13898 inform (0, "%q+D declared here, later in the "
13899 "translation unit", fn);
13903 if (TREE_CODE (function) == IDENTIFIER_NODE)
13905 unqualified_name_lookup_error (function);
13906 release_tree_vector (call_args);
13907 return error_mark_node;
13911 /* Remember that there was a reference to this entity. */
13912 if (DECL_P (function))
13913 mark_used (function);
13915 if (TREE_CODE (function) == OFFSET_REF)
13916 ret = build_offset_ref_call_from_tree (function, &call_args);
13917 else if (TREE_CODE (function) == COMPONENT_REF)
13919 tree instance = TREE_OPERAND (function, 0);
13920 tree fn = TREE_OPERAND (function, 1);
13922 if (processing_template_decl
13923 && (type_dependent_expression_p (instance)
13924 || (!BASELINK_P (fn)
13925 && TREE_CODE (fn) != FIELD_DECL)
13926 || type_dependent_expression_p (fn)
13927 || any_type_dependent_arguments_p (call_args)))
13928 ret = build_nt_call_vec (function, call_args);
13929 else if (!BASELINK_P (fn))
13930 ret = finish_call_expr (function, &call_args,
13931 /*disallow_virtual=*/false,
13932 /*koenig_p=*/false,
13935 ret = (build_new_method_call
13937 &call_args, NULL_TREE,
13938 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13943 ret = finish_call_expr (function, &call_args,
13944 /*disallow_virtual=*/qualified_p,
13948 release_tree_vector (call_args);
13954 return build_x_conditional_expr
13955 (RECUR (TREE_OPERAND (t, 0)),
13956 RECUR (TREE_OPERAND (t, 1)),
13957 RECUR (TREE_OPERAND (t, 2)),
13960 case PSEUDO_DTOR_EXPR:
13961 return finish_pseudo_destructor_expr
13962 (RECUR (TREE_OPERAND (t, 0)),
13963 RECUR (TREE_OPERAND (t, 1)),
13964 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
13968 tree purpose, value, chain;
13970 if (t == void_list_node)
13973 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
13974 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
13976 /* We have pack expansions, so expand those and
13977 create a new list out of it. */
13978 tree purposevec = NULL_TREE;
13979 tree valuevec = NULL_TREE;
13983 /* Expand the argument expressions. */
13984 if (TREE_PURPOSE (t))
13985 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
13986 complain, in_decl);
13987 if (TREE_VALUE (t))
13988 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
13989 complain, in_decl);
13991 /* Build the rest of the list. */
13992 chain = TREE_CHAIN (t);
13993 if (chain && chain != void_type_node)
13994 chain = RECUR (chain);
13996 /* Determine the number of arguments. */
13997 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
13999 len = TREE_VEC_LENGTH (purposevec);
14000 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
14002 else if (TREE_CODE (valuevec) == TREE_VEC)
14003 len = TREE_VEC_LENGTH (valuevec);
14006 /* Since we only performed a partial substitution into
14007 the argument pack, we only return a single list
14009 if (purposevec == TREE_PURPOSE (t)
14010 && valuevec == TREE_VALUE (t)
14011 && chain == TREE_CHAIN (t))
14014 return tree_cons (purposevec, valuevec, chain);
14017 /* Convert the argument vectors into a TREE_LIST */
14021 /* Grab the Ith values. */
14023 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
14026 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
14029 /* Build the list (backwards). */
14030 chain = tree_cons (purpose, value, chain);
14036 purpose = TREE_PURPOSE (t);
14038 purpose = RECUR (purpose);
14039 value = TREE_VALUE (t);
14041 value = RECUR (value);
14042 chain = TREE_CHAIN (t);
14043 if (chain && chain != void_type_node)
14044 chain = RECUR (chain);
14045 if (purpose == TREE_PURPOSE (t)
14046 && value == TREE_VALUE (t)
14047 && chain == TREE_CHAIN (t))
14049 return tree_cons (purpose, value, chain);
14052 case COMPONENT_REF:
14058 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
14059 args, complain, in_decl);
14060 /* Remember that there was a reference to this entity. */
14061 if (DECL_P (object))
14062 mark_used (object);
14063 object_type = TREE_TYPE (object);
14065 member = TREE_OPERAND (t, 1);
14066 if (BASELINK_P (member))
14067 member = tsubst_baselink (member,
14068 non_reference (TREE_TYPE (object)),
14069 args, complain, in_decl);
14071 member = tsubst_copy (member, args, complain, in_decl);
14072 if (member == error_mark_node)
14073 return error_mark_node;
14075 if (type_dependent_expression_p (object))
14076 /* We can't do much here. */;
14077 else if (!CLASS_TYPE_P (object_type))
14079 if (SCALAR_TYPE_P (object_type))
14081 tree s = NULL_TREE;
14082 tree dtor = member;
14084 if (TREE_CODE (dtor) == SCOPE_REF)
14086 s = TREE_OPERAND (dtor, 0);
14087 dtor = TREE_OPERAND (dtor, 1);
14089 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
14091 dtor = TREE_OPERAND (dtor, 0);
14093 return finish_pseudo_destructor_expr (object, s, dtor);
14097 else if (TREE_CODE (member) == SCOPE_REF
14098 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
14100 /* Lookup the template functions now that we know what the
14102 tree scope = TREE_OPERAND (member, 0);
14103 tree tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
14104 tree args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
14105 member = lookup_qualified_name (scope, tmpl,
14106 /*is_type_p=*/false,
14107 /*complain=*/false);
14108 if (BASELINK_P (member))
14110 BASELINK_FUNCTIONS (member)
14111 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
14113 member = (adjust_result_of_qualified_name_lookup
14114 (member, BINFO_TYPE (BASELINK_BINFO (member)),
14119 qualified_name_lookup_error (scope, tmpl, member,
14121 return error_mark_node;
14124 else if (TREE_CODE (member) == SCOPE_REF
14125 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
14126 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
14128 if (complain & tf_error)
14130 if (TYPE_P (TREE_OPERAND (member, 0)))
14131 error ("%qT is not a class or namespace",
14132 TREE_OPERAND (member, 0));
14134 error ("%qD is not a class or namespace",
14135 TREE_OPERAND (member, 0));
14137 return error_mark_node;
14139 else if (TREE_CODE (member) == FIELD_DECL)
14140 return finish_non_static_data_member (member, object, NULL_TREE);
14142 return finish_class_member_access_expr (object, member,
14143 /*template_p=*/false,
14149 (RECUR (TREE_OPERAND (t, 0)));
14153 VEC(constructor_elt,gc) *n;
14154 constructor_elt *ce;
14155 unsigned HOST_WIDE_INT idx;
14156 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
14157 bool process_index_p;
14159 bool need_copy_p = false;
14162 if (type == error_mark_node)
14163 return error_mark_node;
14165 /* digest_init will do the wrong thing if we let it. */
14166 if (type && TYPE_PTRMEMFUNC_P (type))
14169 /* We do not want to process the index of aggregate
14170 initializers as they are identifier nodes which will be
14171 looked up by digest_init. */
14172 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
14174 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
14175 newlen = VEC_length (constructor_elt, n);
14176 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
14178 if (ce->index && process_index_p)
14179 ce->index = RECUR (ce->index);
14181 if (PACK_EXPANSION_P (ce->value))
14183 /* Substitute into the pack expansion. */
14184 ce->value = tsubst_pack_expansion (ce->value, args, complain,
14187 if (ce->value == error_mark_node
14188 || PACK_EXPANSION_P (ce->value))
14190 else if (TREE_VEC_LENGTH (ce->value) == 1)
14191 /* Just move the argument into place. */
14192 ce->value = TREE_VEC_ELT (ce->value, 0);
14195 /* Update the length of the final CONSTRUCTOR
14196 arguments vector, and note that we will need to
14198 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
14199 need_copy_p = true;
14203 ce->value = RECUR (ce->value);
14208 VEC(constructor_elt,gc) *old_n = n;
14210 n = VEC_alloc (constructor_elt, gc, newlen);
14211 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
14213 if (TREE_CODE (ce->value) == TREE_VEC)
14215 int i, len = TREE_VEC_LENGTH (ce->value);
14216 for (i = 0; i < len; ++i)
14217 CONSTRUCTOR_APPEND_ELT (n, 0,
14218 TREE_VEC_ELT (ce->value, i));
14221 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
14225 r = build_constructor (init_list_type_node, n);
14226 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
14228 if (TREE_HAS_CONSTRUCTOR (t))
14229 return finish_compound_literal (type, r, complain);
14231 TREE_TYPE (r) = type;
14237 tree operand_0 = TREE_OPERAND (t, 0);
14238 if (TYPE_P (operand_0))
14240 operand_0 = tsubst (operand_0, args, complain, in_decl);
14241 return get_typeid (operand_0);
14245 operand_0 = RECUR (operand_0);
14246 return build_typeid (operand_0);
14257 tree r = tsubst_copy (t, args, complain, in_decl);
14259 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
14260 /* If the original type was a reference, we'll be wrapped in
14261 the appropriate INDIRECT_REF. */
14262 r = convert_from_reference (r);
14267 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
14268 tsubst (TREE_TYPE (t), args, complain, in_decl));
14270 case OFFSETOF_EXPR:
14271 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
14275 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
14276 complain, in_decl);
14278 tree type2 = TRAIT_EXPR_TYPE2 (t);
14280 type2 = tsubst_copy (type2, args, complain, in_decl);
14282 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
14287 tree old_stmt_expr = cur_stmt_expr;
14288 tree stmt_expr = begin_stmt_expr ();
14290 cur_stmt_expr = stmt_expr;
14291 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
14292 integral_constant_expression_p);
14293 stmt_expr = finish_stmt_expr (stmt_expr, false);
14294 cur_stmt_expr = old_stmt_expr;
14296 /* If the resulting list of expression statement is empty,
14297 fold it further into void_zero_node. */
14298 if (empty_expr_stmt_p (stmt_expr))
14299 stmt_expr = void_zero_node;
14305 t = tsubst_copy (t, args, complain, in_decl);
14306 /* As in finish_id_expression, we resolve enumeration constants
14307 to their underlying values. */
14308 if (TREE_CODE (t) == CONST_DECL && !processing_template_decl)
14310 used_types_insert (TREE_TYPE (t));
14311 return DECL_INITIAL (t);
14317 tree r = build_lambda_expr ();
14319 tree type = tsubst (LAMBDA_EXPR_CLOSURE (t), args, complain, NULL_TREE);
14320 LAMBDA_EXPR_CLOSURE (r) = type;
14321 CLASSTYPE_LAMBDA_EXPR (type) = r;
14323 LAMBDA_EXPR_LOCATION (r)
14324 = LAMBDA_EXPR_LOCATION (t);
14325 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
14326 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
14327 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
14328 LAMBDA_EXPR_DISCRIMINATOR (r)
14329 = (LAMBDA_EXPR_DISCRIMINATOR (t));
14330 LAMBDA_EXPR_EXTRA_SCOPE (r)
14331 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
14332 if (LAMBDA_EXPR_RETURN_TYPE (t) == dependent_lambda_return_type_node)
14334 LAMBDA_EXPR_RETURN_TYPE (r) = dependent_lambda_return_type_node;
14335 LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (r) = true;
14338 LAMBDA_EXPR_RETURN_TYPE (r)
14339 = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
14341 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE
14342 && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL);
14344 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
14345 determine_visibility (TYPE_NAME (type));
14346 /* Now that we know visibility, instantiate the type so we have a
14347 declaration of the op() for later calls to lambda_function. */
14348 complete_type (type);
14350 /* The capture list refers to closure members, so this needs to
14351 wait until after we finish instantiating the type. */
14352 LAMBDA_EXPR_CAPTURE_LIST (r)
14353 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
14355 return build_lambda_object (r);
14359 /* We can get here for a constant initializer of non-dependent type.
14360 FIXME stop folding in cp_parser_initializer_clause. */
14361 gcc_assert (TREE_CONSTANT (t));
14363 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
14364 TREE_CONSTANT (r) = true;
14368 case TRANSACTION_EXPR:
14369 return tsubst_expr(t, args, complain, in_decl,
14370 integral_constant_expression_p);
14373 /* Handle Objective-C++ constructs, if appropriate. */
14376 = objcp_tsubst_copy_and_build (t, args, complain,
14377 in_decl, /*function_p=*/false);
14381 return tsubst_copy (t, args, complain, in_decl);
14387 /* Verify that the instantiated ARGS are valid. For type arguments,
14388 make sure that the type's linkage is ok. For non-type arguments,
14389 make sure they are constants if they are integral or enumerations.
14390 Emit an error under control of COMPLAIN, and return TRUE on error. */
14393 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
14395 if (ARGUMENT_PACK_P (t))
14397 tree vec = ARGUMENT_PACK_ARGS (t);
14398 int len = TREE_VEC_LENGTH (vec);
14399 bool result = false;
14402 for (i = 0; i < len; ++i)
14403 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
14407 else if (TYPE_P (t))
14409 /* [basic.link]: A name with no linkage (notably, the name
14410 of a class or enumeration declared in a local scope)
14411 shall not be used to declare an entity with linkage.
14412 This implies that names with no linkage cannot be used as
14415 DR 757 relaxes this restriction for C++0x. */
14416 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
14417 : no_linkage_check (t, /*relaxed_p=*/false));
14421 /* DR 488 makes use of a type with no linkage cause
14422 type deduction to fail. */
14423 if (complain & tf_error)
14425 if (TYPE_ANONYMOUS_P (nt))
14426 error ("%qT is/uses anonymous type", t);
14428 error ("template argument for %qD uses local type %qT",
14433 /* In order to avoid all sorts of complications, we do not
14434 allow variably-modified types as template arguments. */
14435 else if (variably_modified_type_p (t, NULL_TREE))
14437 if (complain & tf_error)
14438 error ("%qT is a variably modified type", t);
14442 /* A non-type argument of integral or enumerated type must be a
14444 else if (TREE_TYPE (t)
14445 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
14446 && !TREE_CONSTANT (t))
14448 if (complain & tf_error)
14449 error ("integral expression %qE is not constant", t);
14456 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
14458 int ix, len = DECL_NTPARMS (tmpl);
14459 bool result = false;
14461 for (ix = 0; ix != len; ix++)
14463 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
14466 if (result && (complain & tf_error))
14467 error (" trying to instantiate %qD", tmpl);
14471 /* In C++0x, it's possible to have a function template whose type depends
14472 on itself recursively. This is most obvious with decltype, but can also
14473 occur with enumeration scope (c++/48969). So we need to catch infinite
14474 recursion and reject the substitution at deduction time; this function
14475 will return error_mark_node for any repeated substitution.
14477 This also catches excessive recursion such as when f<N> depends on
14478 f<N-1> across all integers, and returns error_mark_node for all the
14479 substitutions back up to the initial one.
14481 This is, of course, not reentrant. */
14484 deduction_tsubst_fntype (tree fn, tree targs, tsubst_flags_t complain)
14486 static bool excessive_deduction_depth;
14487 static int deduction_depth;
14488 struct pending_template *old_last_pend = last_pending_template;
14489 struct tinst_level *old_error_tinst = last_error_tinst_level;
14491 tree fntype = TREE_TYPE (fn);
14495 if (excessive_deduction_depth)
14496 return error_mark_node;
14498 tinst = build_tree_list (fn, targs);
14499 if (!push_tinst_level (tinst))
14501 excessive_deduction_depth = true;
14503 return error_mark_node;
14506 input_location = DECL_SOURCE_LOCATION (fn);
14508 push_deduction_access_scope (fn);
14509 r = tsubst (fntype, targs, complain, NULL_TREE);
14510 pop_deduction_access_scope (fn);
14513 if (excessive_deduction_depth)
14515 r = error_mark_node;
14516 if (deduction_depth == 0)
14517 /* Reset once we're all the way out. */
14518 excessive_deduction_depth = false;
14521 pop_tinst_level ();
14522 /* We can't free this if a pending_template entry or last_error_tinst_level
14523 is pointing at it. */
14524 if (last_pending_template == old_last_pend
14525 && last_error_tinst_level == old_error_tinst)
14530 /* Instantiate the indicated variable or function template TMPL with
14531 the template arguments in TARG_PTR. */
14534 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
14536 tree targ_ptr = orig_args;
14541 if (tmpl == error_mark_node)
14542 return error_mark_node;
14544 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
14546 /* If this function is a clone, handle it specially. */
14547 if (DECL_CLONED_FUNCTION_P (tmpl))
14552 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
14553 DECL_CLONED_FUNCTION. */
14554 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
14555 targ_ptr, complain);
14556 if (spec == error_mark_node)
14557 return error_mark_node;
14559 /* Look for the clone. */
14560 FOR_EACH_CLONE (clone, spec)
14561 if (DECL_NAME (clone) == DECL_NAME (tmpl))
14563 /* We should always have found the clone by now. */
14564 gcc_unreachable ();
14568 /* Check to see if we already have this specialization. */
14569 gen_tmpl = most_general_template (tmpl);
14570 if (tmpl != gen_tmpl)
14571 /* The TMPL is a partial instantiation. To get a full set of
14572 arguments we must add the arguments used to perform the
14573 partial instantiation. */
14574 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
14577 /* It would be nice to avoid hashing here and then again in tsubst_decl,
14578 but it doesn't seem to be on the hot path. */
14579 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
14581 gcc_assert (tmpl == gen_tmpl
14582 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
14584 || fndecl == NULL_TREE);
14586 if (spec != NULL_TREE)
14589 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
14591 return error_mark_node;
14593 /* We are building a FUNCTION_DECL, during which the access of its
14594 parameters and return types have to be checked. However this
14595 FUNCTION_DECL which is the desired context for access checking
14596 is not built yet. We solve this chicken-and-egg problem by
14597 deferring all checks until we have the FUNCTION_DECL. */
14598 push_deferring_access_checks (dk_deferred);
14600 /* Instantiation of the function happens in the context of the function
14601 template, not the context of the overload resolution we're doing. */
14602 push_to_top_level ();
14603 if (DECL_CLASS_SCOPE_P (gen_tmpl))
14605 tree ctx = tsubst (DECL_CONTEXT (gen_tmpl), targ_ptr,
14606 complain, gen_tmpl);
14607 push_nested_class (ctx);
14609 /* Substitute template parameters to obtain the specialization. */
14610 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
14611 targ_ptr, complain, gen_tmpl);
14612 if (DECL_CLASS_SCOPE_P (gen_tmpl))
14613 pop_nested_class ();
14614 pop_from_top_level ();
14616 if (fndecl == error_mark_node)
14617 return error_mark_node;
14619 /* Now we know the specialization, compute access previously
14621 push_access_scope (fndecl);
14623 /* Some typedefs referenced from within the template code need to be access
14624 checked at template instantiation time, i.e now. These types were
14625 added to the template at parsing time. Let's get those and perfom
14626 the acces checks then. */
14627 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
14628 perform_deferred_access_checks ();
14629 pop_access_scope (fndecl);
14630 pop_deferring_access_checks ();
14632 /* The DECL_TI_TEMPLATE should always be the immediate parent
14633 template, not the most general template. */
14634 DECL_TI_TEMPLATE (fndecl) = tmpl;
14636 /* If we've just instantiated the main entry point for a function,
14637 instantiate all the alternate entry points as well. We do this
14638 by cloning the instantiation of the main entry point, not by
14639 instantiating the template clones. */
14640 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
14641 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
14646 /* Wrapper for instantiate_template_1. */
14649 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
14652 timevar_push (TV_TEMPLATE_INST);
14653 ret = instantiate_template_1 (tmpl, orig_args, complain);
14654 timevar_pop (TV_TEMPLATE_INST);
14658 /* We're going to do deduction substitution on the type of TMPL, a function
14659 template. In C++11 mode, push into that access scope. In C++03 mode,
14660 disable access checking. */
14663 push_deduction_access_scope (tree tmpl)
14665 if (cxx_dialect >= cxx0x)
14667 int ptd = processing_template_decl;
14668 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14669 /* Preserve processing_template_decl across push_to_top_level. */
14670 if (ptd && !processing_template_decl)
14671 ++processing_template_decl;
14674 push_deferring_access_checks (dk_no_check);
14677 /* And pop back out. */
14680 pop_deduction_access_scope (tree tmpl)
14682 if (cxx_dialect >= cxx0x)
14683 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14685 pop_deferring_access_checks ();
14688 /* PARM is a template parameter pack for FN. Returns true iff
14689 PARM is used in a deducible way in the argument list of FN. */
14692 pack_deducible_p (tree parm, tree fn)
14694 tree t = FUNCTION_FIRST_USER_PARMTYPE (fn);
14695 for (; t; t = TREE_CHAIN (t))
14697 tree type = TREE_VALUE (t);
14699 if (!PACK_EXPANSION_P (type))
14701 for (packs = PACK_EXPANSION_PARAMETER_PACKS (type);
14702 packs; packs = TREE_CHAIN (packs))
14703 if (TREE_VALUE (packs) == parm)
14705 /* The template parameter pack is used in a function parameter
14706 pack. If this is the end of the parameter list, the
14707 template parameter pack is deducible. */
14708 if (TREE_CHAIN (t) == void_list_node)
14711 /* Otherwise, not. Well, it could be deduced from
14712 a non-pack parameter, but doing so would end up with
14713 a deduction mismatch, so don't bother. */
14717 /* The template parameter pack isn't used in any function parameter
14718 packs, but it might be used deeper, e.g. tuple<Args...>. */
14722 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
14723 NARGS elements of the arguments that are being used when calling
14724 it. TARGS is a vector into which the deduced template arguments
14727 Return zero for success, 2 for an incomplete match that doesn't resolve
14728 all the types, and 1 for complete failure. An error message will be
14729 printed only for an incomplete match.
14731 If FN is a conversion operator, or we are trying to produce a specific
14732 specialization, RETURN_TYPE is the return type desired.
14734 The EXPLICIT_TARGS are explicit template arguments provided via a
14737 The parameter STRICT is one of:
14740 We are deducing arguments for a function call, as in
14741 [temp.deduct.call].
14744 We are deducing arguments for a conversion function, as in
14745 [temp.deduct.conv].
14748 We are deducing arguments when doing an explicit instantiation
14749 as in [temp.explicit], when determining an explicit specialization
14750 as in [temp.expl.spec], or when taking the address of a function
14751 template, as in [temp.deduct.funcaddr]. */
14754 fn_type_unification (tree fn,
14755 tree explicit_targs,
14758 unsigned int nargs,
14760 unification_kind_t strict,
14768 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
14770 fntype = TREE_TYPE (fn);
14771 if (explicit_targs)
14775 The specified template arguments must match the template
14776 parameters in kind (i.e., type, nontype, template), and there
14777 must not be more arguments than there are parameters;
14778 otherwise type deduction fails.
14780 Nontype arguments must match the types of the corresponding
14781 nontype template parameters, or must be convertible to the
14782 types of the corresponding nontype parameters as specified in
14783 _temp.arg.nontype_, otherwise type deduction fails.
14785 All references in the function type of the function template
14786 to the corresponding template parameters are replaced by the
14787 specified template argument values. If a substitution in a
14788 template parameter or in the function type of the function
14789 template results in an invalid type, type deduction fails. */
14790 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
14791 int i, len = TREE_VEC_LENGTH (tparms);
14792 tree converted_args;
14793 bool incomplete = false;
14795 if (explicit_targs == error_mark_node)
14796 return unify_invalid (explain_p);
14799 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE,
14801 ? tf_warning_or_error
14803 /*require_all_args=*/false,
14804 /*use_default_args=*/false));
14805 if (converted_args == error_mark_node)
14808 /* Substitute the explicit args into the function type. This is
14809 necessary so that, for instance, explicitly declared function
14810 arguments can match null pointed constants. If we were given
14811 an incomplete set of explicit args, we must not do semantic
14812 processing during substitution as we could create partial
14814 for (i = 0; i < len; i++)
14816 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14817 bool parameter_pack = false;
14818 tree targ = TREE_VEC_ELT (converted_args, i);
14820 /* Dig out the actual parm. */
14821 if (TREE_CODE (parm) == TYPE_DECL
14822 || TREE_CODE (parm) == TEMPLATE_DECL)
14824 parm = TREE_TYPE (parm);
14825 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
14827 else if (TREE_CODE (parm) == PARM_DECL)
14829 parm = DECL_INITIAL (parm);
14830 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
14833 if (!parameter_pack && targ == NULL_TREE)
14834 /* No explicit argument for this template parameter. */
14837 if (parameter_pack && pack_deducible_p (parm, fn))
14839 /* Mark the argument pack as "incomplete". We could
14840 still deduce more arguments during unification.
14841 We remove this mark in type_unification_real. */
14844 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
14845 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
14846 = ARGUMENT_PACK_ARGS (targ);
14849 /* We have some incomplete argument packs. */
14854 processing_template_decl += incomplete;
14855 fntype = deduction_tsubst_fntype (fn, converted_args,
14857 ? tf_warning_or_error
14859 processing_template_decl -= incomplete;
14861 if (fntype == error_mark_node)
14864 /* Place the explicitly specified arguments in TARGS. */
14865 for (i = NUM_TMPL_ARGS (converted_args); i--;)
14866 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
14869 /* Never do unification on the 'this' parameter. */
14870 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
14876 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
14877 new_args = XALLOCAVEC (tree, nargs + 1);
14878 new_args[0] = return_type;
14879 memcpy (new_args + 1, args, nargs * sizeof (tree));
14884 /* We allow incomplete unification without an error message here
14885 because the standard doesn't seem to explicitly prohibit it. Our
14886 callers must be ready to deal with unification failures in any
14888 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
14889 targs, parms, args, nargs, /*subr=*/0,
14890 strict, flags, explain_p);
14892 /* Now that we have bindings for all of the template arguments,
14893 ensure that the arguments deduced for the template template
14894 parameters have compatible template parameter lists. We cannot
14895 check this property before we have deduced all template
14896 arguments, because the template parameter types of a template
14897 template parameter might depend on prior template parameters
14898 deduced after the template template parameter. The following
14899 ill-formed example illustrates this issue:
14901 template<typename T, template<T> class C> void f(C<5>, T);
14903 template<int N> struct X {};
14906 f(X<5>(), 5l); // error: template argument deduction fails
14909 The template parameter list of 'C' depends on the template type
14910 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
14911 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
14912 time that we deduce 'C'. */
14914 && !template_template_parm_bindings_ok_p
14915 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14916 return unify_inconsistent_template_template_parameters (explain_p);
14919 /* All is well so far. Now, check:
14923 When all template arguments have been deduced, all uses of
14924 template parameters in nondeduced contexts are replaced with
14925 the corresponding deduced argument values. If the
14926 substitution results in an invalid type, as described above,
14927 type deduction fails. */
14929 tree substed = deduction_tsubst_fntype (fn, targs,
14931 ? tf_warning_or_error
14933 if (substed == error_mark_node)
14936 /* If we're looking for an exact match, check that what we got
14937 is indeed an exact match. It might not be if some template
14938 parameters are used in non-deduced contexts. */
14939 if (strict == DEDUCE_EXACT)
14944 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
14946 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
14947 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
14948 if (!same_type_p (args[i], TREE_VALUE (sarg)))
14949 return unify_type_mismatch (explain_p, args[i],
14950 TREE_VALUE (sarg));
14957 /* Adjust types before performing type deduction, as described in
14958 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
14959 sections are symmetric. PARM is the type of a function parameter
14960 or the return type of the conversion function. ARG is the type of
14961 the argument passed to the call, or the type of the value
14962 initialized with the result of the conversion function.
14963 ARG_EXPR is the original argument expression, which may be null. */
14966 maybe_adjust_types_for_deduction (unification_kind_t strict,
14980 /* Swap PARM and ARG throughout the remainder of this
14981 function; the handling is precisely symmetric since PARM
14982 will initialize ARG rather than vice versa. */
14990 /* Core issue #873: Do the DR606 thing (see below) for these cases,
14991 too, but here handle it by stripping the reference from PARM
14992 rather than by adding it to ARG. */
14993 if (TREE_CODE (*parm) == REFERENCE_TYPE
14994 && TYPE_REF_IS_RVALUE (*parm)
14995 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14996 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14997 && TREE_CODE (*arg) == REFERENCE_TYPE
14998 && !TYPE_REF_IS_RVALUE (*arg))
14999 *parm = TREE_TYPE (*parm);
15000 /* Nothing else to do in this case. */
15004 gcc_unreachable ();
15007 if (TREE_CODE (*parm) != REFERENCE_TYPE)
15009 /* [temp.deduct.call]
15011 If P is not a reference type:
15013 --If A is an array type, the pointer type produced by the
15014 array-to-pointer standard conversion (_conv.array_) is
15015 used in place of A for type deduction; otherwise,
15017 --If A is a function type, the pointer type produced by
15018 the function-to-pointer standard conversion
15019 (_conv.func_) is used in place of A for type deduction;
15022 --If A is a cv-qualified type, the top level
15023 cv-qualifiers of A's type are ignored for type
15025 if (TREE_CODE (*arg) == ARRAY_TYPE)
15026 *arg = build_pointer_type (TREE_TYPE (*arg));
15027 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
15028 *arg = build_pointer_type (*arg);
15030 *arg = TYPE_MAIN_VARIANT (*arg);
15033 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
15034 of the form T&&, where T is a template parameter, and the argument
15035 is an lvalue, T is deduced as A& */
15036 if (TREE_CODE (*parm) == REFERENCE_TYPE
15037 && TYPE_REF_IS_RVALUE (*parm)
15038 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
15039 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
15040 && (arg_expr ? real_lvalue_p (arg_expr)
15041 /* try_one_overload doesn't provide an arg_expr, but
15042 functions are always lvalues. */
15043 : TREE_CODE (*arg) == FUNCTION_TYPE))
15044 *arg = build_reference_type (*arg);
15046 /* [temp.deduct.call]
15048 If P is a cv-qualified type, the top level cv-qualifiers
15049 of P's type are ignored for type deduction. If P is a
15050 reference type, the type referred to by P is used for
15052 *parm = TYPE_MAIN_VARIANT (*parm);
15053 if (TREE_CODE (*parm) == REFERENCE_TYPE)
15055 *parm = TREE_TYPE (*parm);
15056 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15059 /* DR 322. For conversion deduction, remove a reference type on parm
15060 too (which has been swapped into ARG). */
15061 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
15062 *arg = TREE_TYPE (*arg);
15067 /* Subroutine of unify_one_argument. PARM is a function parameter of a
15068 template which does contain any deducible template parameters; check if
15069 ARG is a suitable match for it. STRICT, FLAGS and EXPLAIN_P are as in
15070 unify_one_argument. */
15073 check_non_deducible_conversion (tree parm, tree arg, int strict,
15074 int flags, bool explain_p)
15079 type = TREE_TYPE (arg);
15083 if (same_type_p (parm, type))
15084 return unify_success (explain_p);
15086 if (strict == DEDUCE_CONV)
15088 if (can_convert_arg (type, parm, NULL_TREE, flags))
15089 return unify_success (explain_p);
15091 else if (strict != DEDUCE_EXACT)
15093 if (can_convert_arg (parm, type,
15094 TYPE_P (arg) ? NULL_TREE : arg,
15096 return unify_success (explain_p);
15099 if (strict == DEDUCE_EXACT)
15100 return unify_type_mismatch (explain_p, parm, arg);
15102 return unify_arg_conversion (explain_p, parm, type, arg);
15105 /* Subroutine of type_unification_real and unify_pack_expansion to
15106 handle unification of a single P/A pair. Parameters are as
15107 for those functions. */
15110 unify_one_argument (tree tparms, tree targs, tree parm, tree arg,
15111 int subr, unification_kind_t strict, int flags,
15114 tree arg_expr = NULL_TREE;
15117 if (arg == error_mark_node || parm == error_mark_node)
15118 return unify_invalid (explain_p);
15119 if (arg == unknown_type_node)
15120 /* We can't deduce anything from this, but we might get all the
15121 template args from other function args. */
15122 return unify_success (explain_p);
15124 /* FIXME uses_deducible_template_parms */
15125 if (TYPE_P (parm) && !uses_template_parms (parm))
15126 return check_non_deducible_conversion (parm, arg, strict, flags,
15132 arg_strict = (UNIFY_ALLOW_OUTER_LEVEL
15133 | UNIFY_ALLOW_MORE_CV_QUAL
15134 | UNIFY_ALLOW_DERIVED);
15138 arg_strict = UNIFY_ALLOW_LESS_CV_QUAL;
15142 arg_strict = UNIFY_ALLOW_NONE;
15146 gcc_unreachable ();
15149 /* We only do these transformations if this is the top-level
15150 parameter_type_list in a call or declaration matching; in other
15151 situations (nested function declarators, template argument lists) we
15152 won't be comparing a type to an expression, and we don't do any type
15158 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
15159 if (type_unknown_p (arg))
15161 /* [temp.deduct.type] A template-argument can be
15162 deduced from a pointer to function or pointer
15163 to member function argument if the set of
15164 overloaded functions does not contain function
15165 templates and at most one of a set of
15166 overloaded functions provides a unique
15169 if (resolve_overloaded_unification
15170 (tparms, targs, parm, arg, strict,
15171 arg_strict, explain_p))
15172 return unify_success (explain_p);
15173 return unify_overload_resolution_failure (explain_p, arg);
15177 arg = unlowered_expr_type (arg);
15178 if (arg == error_mark_node)
15179 return unify_invalid (explain_p);
15183 maybe_adjust_types_for_deduction (strict, &parm, &arg, arg_expr);
15186 gcc_assert ((TYPE_P (parm) || TREE_CODE (parm) == TEMPLATE_DECL)
15187 == (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL));
15189 /* For deduction from an init-list we need the actual list. */
15190 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15192 return unify (tparms, targs, parm, arg, arg_strict, explain_p);
15195 /* Most parms like fn_type_unification.
15197 If SUBR is 1, we're being called recursively (to unify the
15198 arguments of a function or method parameter of a function
15202 type_unification_real (tree tparms,
15206 unsigned int xnargs,
15208 unification_kind_t strict,
15214 int ntparms = TREE_VEC_LENGTH (tparms);
15215 int saw_undeduced = 0;
15218 unsigned int nargs;
15221 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
15222 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
15223 gcc_assert (ntparms > 0);
15225 /* Reset the number of non-defaulted template arguments contained
15227 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
15235 while (parms && parms != void_list_node
15238 parm = TREE_VALUE (parms);
15240 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
15241 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
15242 /* For a function parameter pack that occurs at the end of the
15243 parameter-declaration-list, the type A of each remaining
15244 argument of the call is compared with the type P of the
15245 declarator-id of the function parameter pack. */
15248 parms = TREE_CHAIN (parms);
15250 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
15251 /* For a function parameter pack that does not occur at the
15252 end of the parameter-declaration-list, the type of the
15253 parameter pack is a non-deduced context. */
15259 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15265 && parms != void_list_node
15266 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
15268 /* Unify the remaining arguments with the pack expansion type. */
15270 tree parmvec = make_tree_vec (1);
15272 /* Allocate a TREE_VEC and copy in all of the arguments */
15273 argvec = make_tree_vec (nargs - ia);
15274 for (i = 0; ia < nargs; ++ia, ++i)
15275 TREE_VEC_ELT (argvec, i) = args[ia];
15277 /* Copy the parameter into parmvec. */
15278 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
15279 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
15280 /*subr=*/subr, explain_p))
15283 /* Advance to the end of the list of parameters. */
15284 parms = TREE_CHAIN (parms);
15287 /* Fail if we've reached the end of the parm list, and more args
15288 are present, and the parm list isn't variadic. */
15289 if (ia < nargs && parms == void_list_node)
15290 return unify_too_many_arguments (explain_p, nargs, ia);
15291 /* Fail if parms are left and they don't have default values. */
15292 if (parms && parms != void_list_node
15293 && TREE_PURPOSE (parms) == NULL_TREE)
15295 unsigned int count = nargs;
15297 while (p && p != void_list_node)
15300 p = TREE_CHAIN (p);
15302 return unify_too_few_arguments (explain_p, ia, count);
15307 tsubst_flags_t complain = (explain_p
15308 ? tf_warning_or_error
15311 /* Check to see if we need another pass before we start clearing
15312 ARGUMENT_PACK_INCOMPLETE_P. */
15313 for (i = 0; i < ntparms; i++)
15315 tree targ = TREE_VEC_ELT (targs, i);
15316 tree tparm = TREE_VEC_ELT (tparms, i);
15318 if (targ || tparm == error_mark_node)
15320 tparm = TREE_VALUE (tparm);
15322 /* If this is an undeduced nontype parameter that depends on
15323 a type parameter, try another pass; its type may have been
15324 deduced from a later argument than the one from which
15325 this parameter can be deduced. */
15326 if (TREE_CODE (tparm) == PARM_DECL
15327 && uses_template_parms (TREE_TYPE (tparm))
15328 && !saw_undeduced++)
15332 for (i = 0; i < ntparms; i++)
15334 tree targ = TREE_VEC_ELT (targs, i);
15335 tree tparm = TREE_VEC_ELT (tparms, i);
15337 /* Clear the "incomplete" flags on all argument packs now so that
15338 substituting them into later default arguments works. */
15339 if (targ && ARGUMENT_PACK_P (targ))
15341 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
15342 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
15345 if (targ || tparm == error_mark_node)
15347 tparm = TREE_VALUE (tparm);
15349 /* Core issue #226 (C++0x) [temp.deduct]:
15351 If a template argument has not been deduced, its
15352 default template argument, if any, is used.
15354 When we are in C++98 mode, TREE_PURPOSE will either
15355 be NULL_TREE or ERROR_MARK_NODE, so we do not need
15356 to explicitly check cxx_dialect here. */
15357 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
15359 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
15360 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
15361 location_t save_loc = input_location;
15363 input_location = DECL_SOURCE_LOCATION (parm);
15364 arg = tsubst_template_arg (arg, targs, complain, NULL_TREE);
15365 arg = convert_template_argument (parm, arg, targs, complain,
15367 input_location = save_loc;
15368 if (arg == error_mark_node)
15372 TREE_VEC_ELT (targs, i) = arg;
15373 /* The position of the first default template argument,
15374 is also the number of non-defaulted arguments in TARGS.
15376 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15377 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
15382 /* If the type parameter is a parameter pack, then it will
15383 be deduced to an empty parameter pack. */
15384 if (template_parameter_pack_p (tparm))
15388 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
15390 arg = make_node (NONTYPE_ARGUMENT_PACK);
15391 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
15392 TREE_CONSTANT (arg) = 1;
15395 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
15397 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
15399 TREE_VEC_ELT (targs, i) = arg;
15403 return unify_parameter_deduction_failure (explain_p, tparm);
15406 #ifdef ENABLE_CHECKING
15407 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15408 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
15411 return unify_success (explain_p);
15414 /* Subroutine of type_unification_real. Args are like the variables
15415 at the call site. ARG is an overloaded function (or template-id);
15416 we try deducing template args from each of the overloads, and if
15417 only one succeeds, we go with that. Modifies TARGS and returns
15418 true on success. */
15421 resolve_overloaded_unification (tree tparms,
15425 unification_kind_t strict,
15429 tree tempargs = copy_node (targs);
15431 tree goodfn = NULL_TREE;
15434 if (TREE_CODE (arg) == ADDR_EXPR)
15436 arg = TREE_OPERAND (arg, 0);
15442 if (TREE_CODE (arg) == COMPONENT_REF)
15443 /* Handle `&x' where `x' is some static or non-static member
15445 arg = TREE_OPERAND (arg, 1);
15447 if (TREE_CODE (arg) == OFFSET_REF)
15448 arg = TREE_OPERAND (arg, 1);
15450 /* Strip baselink information. */
15451 if (BASELINK_P (arg))
15452 arg = BASELINK_FUNCTIONS (arg);
15454 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
15456 /* If we got some explicit template args, we need to plug them into
15457 the affected templates before we try to unify, in case the
15458 explicit args will completely resolve the templates in question. */
15461 tree expl_subargs = TREE_OPERAND (arg, 1);
15462 arg = TREE_OPERAND (arg, 0);
15464 for (; arg; arg = OVL_NEXT (arg))
15466 tree fn = OVL_CURRENT (arg);
15467 tree subargs, elem;
15469 if (TREE_CODE (fn) != TEMPLATE_DECL)
15472 ++processing_template_decl;
15473 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15474 expl_subargs, /*check_ret=*/false);
15475 if (subargs && !any_dependent_template_arguments_p (subargs))
15477 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
15478 if (try_one_overload (tparms, targs, tempargs, parm,
15479 elem, strict, sub_strict, addr_p, explain_p)
15480 && (!goodfn || !same_type_p (goodfn, elem)))
15488 --processing_template_decl;
15490 /* If no templates (or more than one) are fully resolved by the
15491 explicit arguments, this template-id is a non-deduced context; it
15492 could still be OK if we deduce all template arguments for the
15493 enclosing call through other arguments. */
15497 else if (TREE_CODE (arg) != OVERLOAD
15498 && TREE_CODE (arg) != FUNCTION_DECL)
15499 /* If ARG is, for example, "(0, &f)" then its type will be unknown
15500 -- but the deduction does not succeed because the expression is
15501 not just the function on its own. */
15504 for (; arg; arg = OVL_NEXT (arg))
15505 if (try_one_overload (tparms, targs, tempargs, parm,
15506 TREE_TYPE (OVL_CURRENT (arg)),
15507 strict, sub_strict, addr_p, explain_p)
15508 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
15510 goodfn = OVL_CURRENT (arg);
15514 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15515 to function or pointer to member function argument if the set of
15516 overloaded functions does not contain function templates and at most
15517 one of a set of overloaded functions provides a unique match.
15519 So if we found multiple possibilities, we return success but don't
15520 deduce anything. */
15524 int i = TREE_VEC_LENGTH (targs);
15526 if (TREE_VEC_ELT (tempargs, i))
15527 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
15535 /* Core DR 115: In contexts where deduction is done and fails, or in
15536 contexts where deduction is not done, if a template argument list is
15537 specified and it, along with any default template arguments, identifies
15538 a single function template specialization, then the template-id is an
15539 lvalue for the function template specialization. */
15542 resolve_nondeduced_context (tree orig_expr)
15544 tree expr, offset, baselink;
15547 if (!type_unknown_p (orig_expr))
15552 offset = NULL_TREE;
15553 baselink = NULL_TREE;
15555 if (TREE_CODE (expr) == ADDR_EXPR)
15557 expr = TREE_OPERAND (expr, 0);
15560 if (TREE_CODE (expr) == OFFSET_REF)
15563 expr = TREE_OPERAND (expr, 1);
15565 if (BASELINK_P (expr))
15568 expr = BASELINK_FUNCTIONS (expr);
15571 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
15574 tree goodfn = NULL_TREE;
15576 /* If we got some explicit template args, we need to plug them into
15577 the affected templates before we try to unify, in case the
15578 explicit args will completely resolve the templates in question. */
15580 tree expl_subargs = TREE_OPERAND (expr, 1);
15581 tree arg = TREE_OPERAND (expr, 0);
15582 tree badfn = NULL_TREE;
15583 tree badargs = NULL_TREE;
15585 for (; arg; arg = OVL_NEXT (arg))
15587 tree fn = OVL_CURRENT (arg);
15588 tree subargs, elem;
15590 if (TREE_CODE (fn) != TEMPLATE_DECL)
15593 ++processing_template_decl;
15594 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15595 expl_subargs, /*check_ret=*/false);
15596 if (subargs && !any_dependent_template_arguments_p (subargs))
15598 elem = instantiate_template (fn, subargs, tf_none);
15599 if (elem == error_mark_node)
15604 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
15610 --processing_template_decl;
15614 mark_used (goodfn);
15617 expr = build_baselink (BASELINK_BINFO (baselink),
15618 BASELINK_ACCESS_BINFO (baselink),
15619 expr, BASELINK_OPTYPE (baselink));
15623 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
15624 expr = build_offset_ref (base, expr, addr);
15627 expr = cp_build_addr_expr (expr, tf_warning_or_error);
15630 else if (good == 0 && badargs)
15631 /* There were no good options and at least one bad one, so let the
15632 user know what the problem is. */
15633 instantiate_template (badfn, badargs, tf_warning_or_error);
15638 /* Subroutine of resolve_overloaded_unification; does deduction for a single
15639 overload. Fills TARGS with any deduced arguments, or error_mark_node if
15640 different overloads deduce different arguments for a given parm.
15641 ADDR_P is true if the expression for which deduction is being
15642 performed was of the form "& fn" rather than simply "fn".
15644 Returns 1 on success. */
15647 try_one_overload (tree tparms,
15652 unification_kind_t strict,
15661 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15662 to function or pointer to member function argument if the set of
15663 overloaded functions does not contain function templates and at most
15664 one of a set of overloaded functions provides a unique match.
15666 So if this is a template, just return success. */
15668 if (uses_template_parms (arg))
15671 if (TREE_CODE (arg) == METHOD_TYPE)
15672 arg = build_ptrmemfunc_type (build_pointer_type (arg));
15674 arg = build_pointer_type (arg);
15676 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
15678 /* We don't copy orig_targs for this because if we have already deduced
15679 some template args from previous args, unify would complain when we
15680 try to deduce a template parameter for the same argument, even though
15681 there isn't really a conflict. */
15682 nargs = TREE_VEC_LENGTH (targs);
15683 tempargs = make_tree_vec (nargs);
15685 if (unify (tparms, tempargs, parm, arg, sub_strict, explain_p))
15688 /* First make sure we didn't deduce anything that conflicts with
15689 explicitly specified args. */
15690 for (i = nargs; i--; )
15692 tree elt = TREE_VEC_ELT (tempargs, i);
15693 tree oldelt = TREE_VEC_ELT (orig_targs, i);
15697 else if (uses_template_parms (elt))
15698 /* Since we're unifying against ourselves, we will fill in
15699 template args used in the function parm list with our own
15700 template parms. Discard them. */
15701 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
15702 else if (oldelt && !template_args_equal (oldelt, elt))
15706 for (i = nargs; i--; )
15708 tree elt = TREE_VEC_ELT (tempargs, i);
15711 TREE_VEC_ELT (targs, i) = elt;
15717 /* PARM is a template class (perhaps with unbound template
15718 parameters). ARG is a fully instantiated type. If ARG can be
15719 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
15720 TARGS are as for unify. */
15723 try_class_unification (tree tparms, tree targs, tree parm, tree arg,
15726 tree copy_of_targs;
15728 if (!CLASSTYPE_TEMPLATE_INFO (arg)
15729 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
15730 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
15733 /* We need to make a new template argument vector for the call to
15734 unify. If we used TARGS, we'd clutter it up with the result of
15735 the attempted unification, even if this class didn't work out.
15736 We also don't want to commit ourselves to all the unifications
15737 we've already done, since unification is supposed to be done on
15738 an argument-by-argument basis. In other words, consider the
15739 following pathological case:
15741 template <int I, int J, int K>
15744 template <int I, int J>
15745 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
15747 template <int I, int J, int K>
15748 void f(S<I, J, K>, S<I, I, I>);
15757 Now, by the time we consider the unification involving `s2', we
15758 already know that we must have `f<0, 0, 0>'. But, even though
15759 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
15760 because there are two ways to unify base classes of S<0, 1, 2>
15761 with S<I, I, I>. If we kept the already deduced knowledge, we
15762 would reject the possibility I=1. */
15763 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
15765 /* If unification failed, we're done. */
15766 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
15767 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p))
15773 /* Given a template type PARM and a class type ARG, find the unique
15774 base type in ARG that is an instance of PARM. We do not examine
15775 ARG itself; only its base-classes. If there is not exactly one
15776 appropriate base class, return NULL_TREE. PARM may be the type of
15777 a partial specialization, as well as a plain template type. Used
15780 static enum template_base_result
15781 get_template_base (tree tparms, tree targs, tree parm, tree arg,
15782 bool explain_p, tree *result)
15784 tree rval = NULL_TREE;
15787 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
15789 binfo = TYPE_BINFO (complete_type (arg));
15792 /* The type could not be completed. */
15793 *result = NULL_TREE;
15794 return tbr_incomplete_type;
15797 /* Walk in inheritance graph order. The search order is not
15798 important, and this avoids multiple walks of virtual bases. */
15799 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
15801 tree r = try_class_unification (tparms, targs, parm,
15802 BINFO_TYPE (binfo), explain_p);
15806 /* If there is more than one satisfactory baseclass, then:
15810 If they yield more than one possible deduced A, the type
15814 if (rval && !same_type_p (r, rval))
15816 *result = NULL_TREE;
15817 return tbr_ambiguous_baseclass;
15825 return tbr_success;
15828 /* Returns the level of DECL, which declares a template parameter. */
15831 template_decl_level (tree decl)
15833 switch (TREE_CODE (decl))
15836 case TEMPLATE_DECL:
15837 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
15840 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
15843 gcc_unreachable ();
15848 /* Decide whether ARG can be unified with PARM, considering only the
15849 cv-qualifiers of each type, given STRICT as documented for unify.
15850 Returns nonzero iff the unification is OK on that basis. */
15853 check_cv_quals_for_unify (int strict, tree arg, tree parm)
15855 int arg_quals = cp_type_quals (arg);
15856 int parm_quals = cp_type_quals (parm);
15858 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15859 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15861 /* Although a CVR qualifier is ignored when being applied to a
15862 substituted template parameter ([8.3.2]/1 for example), that
15863 does not allow us to unify "const T" with "int&" because both
15864 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
15865 It is ok when we're allowing additional CV qualifiers
15866 at the outer level [14.8.2.1]/3,1st bullet. */
15867 if ((TREE_CODE (arg) == REFERENCE_TYPE
15868 || TREE_CODE (arg) == FUNCTION_TYPE
15869 || TREE_CODE (arg) == METHOD_TYPE)
15870 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
15873 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
15874 && (parm_quals & TYPE_QUAL_RESTRICT))
15878 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15879 && (arg_quals & parm_quals) != parm_quals)
15882 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
15883 && (parm_quals & arg_quals) != arg_quals)
15889 /* Determines the LEVEL and INDEX for the template parameter PARM. */
15891 template_parm_level_and_index (tree parm, int* level, int* index)
15893 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15894 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15895 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15897 *index = TEMPLATE_TYPE_IDX (parm);
15898 *level = TEMPLATE_TYPE_LEVEL (parm);
15902 *index = TEMPLATE_PARM_IDX (parm);
15903 *level = TEMPLATE_PARM_LEVEL (parm);
15907 #define RECUR_AND_CHECK_FAILURE(TP, TA, P, A, S, EP) \
15909 if (unify (TP, TA, P, A, S, EP)) \
15913 /* Unifies the remaining arguments in PACKED_ARGS with the pack
15914 expansion at the end of PACKED_PARMS. Returns 0 if the type
15915 deduction succeeds, 1 otherwise. STRICT is the same as in
15916 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
15917 call argument list. We'll need to adjust the arguments to make them
15918 types. SUBR tells us if this is from a recursive call to
15919 type_unification_real, or for comparing two template argument
15923 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
15924 tree packed_args, unification_kind_t strict,
15925 bool subr, bool explain_p)
15928 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
15929 tree pattern = PACK_EXPANSION_PATTERN (parm);
15930 tree pack, packs = NULL_TREE;
15931 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
15932 int len = TREE_VEC_LENGTH (packed_args);
15934 /* Determine the parameter packs we will be deducing from the
15935 pattern, and record their current deductions. */
15936 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
15937 pack; pack = TREE_CHAIN (pack))
15939 tree parm_pack = TREE_VALUE (pack);
15942 /* Determine the index and level of this parameter pack. */
15943 template_parm_level_and_index (parm_pack, &level, &idx);
15945 /* Keep track of the parameter packs and their corresponding
15947 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
15948 TREE_TYPE (packs) = make_tree_vec (len - start);
15951 /* Loop through all of the arguments that have not yet been
15952 unified and unify each with the pattern. */
15953 for (i = start; i < len; i++)
15956 bool any_explicit = false;
15957 tree arg = TREE_VEC_ELT (packed_args, i);
15959 /* For each parameter pack, set its TMPL_ARG to either NULL_TREE
15960 or the element of its argument pack at the current index if
15961 this argument was explicitly specified. */
15962 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15966 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15969 if (TREE_VALUE (pack)
15970 && (pargs = ARGUMENT_PACK_EXPLICIT_ARGS (TREE_VALUE (pack)))
15971 && (i < TREE_VEC_LENGTH (pargs)))
15973 any_explicit = true;
15974 arg = TREE_VEC_ELT (pargs, i);
15976 TMPL_ARG (targs, level, idx) = arg;
15979 /* If we had explicit template arguments, substitute them into the
15980 pattern before deduction. */
15983 /* Some arguments might still be unspecified or dependent. */
15985 ++processing_template_decl;
15986 dependent = any_dependent_template_arguments_p (targs);
15988 --processing_template_decl;
15989 parm = tsubst (pattern, targs,
15990 explain_p ? tf_warning_or_error : tf_none,
15993 --processing_template_decl;
15994 if (parm == error_mark_node)
16000 /* Unify the pattern with the current argument. */
16001 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
16002 LOOKUP_IMPLICIT, explain_p))
16005 /* For each parameter pack, collect the deduced value. */
16006 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16009 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16011 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
16012 TMPL_ARG (targs, level, idx);
16016 /* Verify that the results of unification with the parameter packs
16017 produce results consistent with what we've seen before, and make
16018 the deduced argument packs available. */
16019 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16021 tree old_pack = TREE_VALUE (pack);
16022 tree new_args = TREE_TYPE (pack);
16023 int i, len = TREE_VEC_LENGTH (new_args);
16025 bool nondeduced_p = false;
16027 /* By default keep the original deduced argument pack.
16028 If necessary, more specific code is going to update the
16029 resulting deduced argument later down in this function. */
16030 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16031 TMPL_ARG (targs, level, idx) = old_pack;
16033 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
16034 actually deduce anything. */
16035 for (i = 0; i < len && !nondeduced_p; ++i)
16036 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
16037 nondeduced_p = true;
16041 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
16043 /* If we had fewer function args than explicit template args,
16044 just use the explicits. */
16045 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16046 int explicit_len = TREE_VEC_LENGTH (explicit_args);
16047 if (len < explicit_len)
16048 new_args = explicit_args;
16054 /* Build the deduced *_ARGUMENT_PACK. */
16055 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
16057 result = make_node (NONTYPE_ARGUMENT_PACK);
16058 TREE_TYPE (result) =
16059 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
16060 TREE_CONSTANT (result) = 1;
16063 result = cxx_make_type (TYPE_ARGUMENT_PACK);
16065 SET_ARGUMENT_PACK_ARGS (result, new_args);
16067 /* Note the deduced argument packs for this parameter
16069 TMPL_ARG (targs, level, idx) = result;
16071 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
16072 && (ARGUMENT_PACK_ARGS (old_pack)
16073 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
16075 /* We only had the explicitly-provided arguments before, but
16076 now we have a complete set of arguments. */
16077 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16079 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
16080 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
16081 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
16085 tree bad_old_arg = NULL_TREE, bad_new_arg = NULL_TREE;
16086 tree old_args = ARGUMENT_PACK_ARGS (old_pack);
16088 if (!comp_template_args_with_info (old_args, new_args,
16089 &bad_old_arg, &bad_new_arg))
16090 /* Inconsistent unification of this parameter pack. */
16091 return unify_parameter_pack_inconsistent (explain_p,
16097 return unify_success (explain_p);
16100 /* Deduce the value of template parameters. TPARMS is the (innermost)
16101 set of template parameters to a template. TARGS is the bindings
16102 for those template parameters, as determined thus far; TARGS may
16103 include template arguments for outer levels of template parameters
16104 as well. PARM is a parameter to a template function, or a
16105 subcomponent of that parameter; ARG is the corresponding argument.
16106 This function attempts to match PARM with ARG in a manner
16107 consistent with the existing assignments in TARGS. If more values
16108 are deduced, then TARGS is updated.
16110 Returns 0 if the type deduction succeeds, 1 otherwise. The
16111 parameter STRICT is a bitwise or of the following flags:
16114 Require an exact match between PARM and ARG.
16115 UNIFY_ALLOW_MORE_CV_QUAL:
16116 Allow the deduced ARG to be more cv-qualified (by qualification
16117 conversion) than ARG.
16118 UNIFY_ALLOW_LESS_CV_QUAL:
16119 Allow the deduced ARG to be less cv-qualified than ARG.
16120 UNIFY_ALLOW_DERIVED:
16121 Allow the deduced ARG to be a template base class of ARG,
16122 or a pointer to a template base class of the type pointed to by
16124 UNIFY_ALLOW_INTEGER:
16125 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
16126 case for more information.
16127 UNIFY_ALLOW_OUTER_LEVEL:
16128 This is the outermost level of a deduction. Used to determine validity
16129 of qualification conversions. A valid qualification conversion must
16130 have const qualified pointers leading up to the inner type which
16131 requires additional CV quals, except at the outer level, where const
16132 is not required [conv.qual]. It would be normal to set this flag in
16133 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
16134 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
16135 This is the outermost level of a deduction, and PARM can be more CV
16136 qualified at this point.
16137 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
16138 This is the outermost level of a deduction, and PARM can be less CV
16139 qualified at this point. */
16142 unify (tree tparms, tree targs, tree parm, tree arg, int strict,
16148 int strict_in = strict;
16150 /* I don't think this will do the right thing with respect to types.
16151 But the only case I've seen it in so far has been array bounds, where
16152 signedness is the only information lost, and I think that will be
16154 while (TREE_CODE (parm) == NOP_EXPR)
16155 parm = TREE_OPERAND (parm, 0);
16157 if (arg == error_mark_node)
16158 return unify_invalid (explain_p);
16159 if (arg == unknown_type_node
16160 || arg == init_list_type_node)
16161 /* We can't deduce anything from this, but we might get all the
16162 template args from other function args. */
16163 return unify_success (explain_p);
16165 /* If PARM uses template parameters, then we can't bail out here,
16166 even if ARG == PARM, since we won't record unifications for the
16167 template parameters. We might need them if we're trying to
16168 figure out which of two things is more specialized. */
16169 if (arg == parm && !uses_template_parms (parm))
16170 return unify_success (explain_p);
16172 /* Handle init lists early, so the rest of the function can assume
16173 we're dealing with a type. */
16174 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
16178 tree orig_parm = parm;
16180 /* Replace T with std::initializer_list<T> for deduction. */
16181 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16182 && flag_deduce_init_list)
16183 parm = listify (parm);
16185 if (!is_std_init_list (parm))
16186 /* We can only deduce from an initializer list argument if the
16187 parameter is std::initializer_list; otherwise this is a
16188 non-deduced context. */
16189 return unify_success (explain_p);
16191 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
16193 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
16195 int elt_strict = strict;
16197 if (elt == error_mark_node)
16198 return unify_invalid (explain_p);
16200 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
16202 tree type = TREE_TYPE (elt);
16203 /* It should only be possible to get here for a call. */
16204 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
16205 elt_strict |= maybe_adjust_types_for_deduction
16206 (DEDUCE_CALL, &elttype, &type, elt);
16210 RECUR_AND_CHECK_FAILURE (tparms, targs, elttype, elt, elt_strict,
16214 /* If the std::initializer_list<T> deduction worked, replace the
16215 deduced A with std::initializer_list<A>. */
16216 if (orig_parm != parm)
16218 idx = TEMPLATE_TYPE_IDX (orig_parm);
16219 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16220 targ = listify (targ);
16221 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
16223 return unify_success (explain_p);
16226 /* Immediately reject some pairs that won't unify because of
16227 cv-qualification mismatches. */
16228 if (TREE_CODE (arg) == TREE_CODE (parm)
16230 /* It is the elements of the array which hold the cv quals of an array
16231 type, and the elements might be template type parms. We'll check
16232 when we recurse. */
16233 && TREE_CODE (arg) != ARRAY_TYPE
16234 /* We check the cv-qualifiers when unifying with template type
16235 parameters below. We want to allow ARG `const T' to unify with
16236 PARM `T' for example, when computing which of two templates
16237 is more specialized, for example. */
16238 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
16239 && !check_cv_quals_for_unify (strict_in, arg, parm))
16240 return unify_cv_qual_mismatch (explain_p, parm, arg);
16242 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
16243 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
16244 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
16245 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
16246 strict &= ~UNIFY_ALLOW_DERIVED;
16247 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
16248 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
16250 switch (TREE_CODE (parm))
16252 case TYPENAME_TYPE:
16254 case UNBOUND_CLASS_TEMPLATE:
16255 /* In a type which contains a nested-name-specifier, template
16256 argument values cannot be deduced for template parameters used
16257 within the nested-name-specifier. */
16258 return unify_success (explain_p);
16260 case TEMPLATE_TYPE_PARM:
16261 case TEMPLATE_TEMPLATE_PARM:
16262 case BOUND_TEMPLATE_TEMPLATE_PARM:
16263 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16264 if (tparm == error_mark_node)
16265 return unify_invalid (explain_p);
16267 if (TEMPLATE_TYPE_LEVEL (parm)
16268 != template_decl_level (tparm))
16269 /* The PARM is not one we're trying to unify. Just check
16270 to see if it matches ARG. */
16272 if (TREE_CODE (arg) == TREE_CODE (parm)
16273 && same_type_p (parm, arg))
16274 return unify_success (explain_p);
16276 return unify_type_mismatch (explain_p, parm, arg);
16278 idx = TEMPLATE_TYPE_IDX (parm);
16279 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16280 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
16281 if (tparm == error_mark_node)
16282 return unify_invalid (explain_p);
16284 /* Check for mixed types and values. */
16285 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16286 && TREE_CODE (tparm) != TYPE_DECL)
16287 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16288 && TREE_CODE (tparm) != TEMPLATE_DECL))
16289 gcc_unreachable ();
16291 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16293 /* ARG must be constructed from a template class or a template
16294 template parameter. */
16295 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
16296 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
16297 return unify_template_deduction_failure (explain_p, parm, arg);
16300 tree parmvec = TYPE_TI_ARGS (parm);
16301 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
16302 tree full_argvec = add_to_template_args (targs, argvec);
16304 = DECL_INNERMOST_TEMPLATE_PARMS
16305 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
16307 int parm_variadic_p = 0;
16309 /* The resolution to DR150 makes clear that default
16310 arguments for an N-argument may not be used to bind T
16311 to a template template parameter with fewer than N
16312 parameters. It is not safe to permit the binding of
16313 default arguments as an extension, as that may change
16314 the meaning of a conforming program. Consider:
16316 struct Dense { static const unsigned int dim = 1; };
16318 template <template <typename> class View,
16320 void operator+(float, View<Block> const&);
16322 template <typename Block,
16323 unsigned int Dim = Block::dim>
16324 struct Lvalue_proxy { operator float() const; };
16328 Lvalue_proxy<Dense> p;
16333 Here, if Lvalue_proxy is permitted to bind to View, then
16334 the global operator+ will be used; if they are not, the
16335 Lvalue_proxy will be converted to float. */
16336 if (coerce_template_parms (parm_parms,
16338 TYPE_TI_TEMPLATE (parm),
16340 ? tf_warning_or_error
16342 /*require_all_args=*/true,
16343 /*use_default_args=*/false)
16344 == error_mark_node)
16347 /* Deduce arguments T, i from TT<T> or TT<i>.
16348 We check each element of PARMVEC and ARGVEC individually
16349 rather than the whole TREE_VEC since they can have
16350 different number of elements. */
16352 parmvec = expand_template_argument_pack (parmvec);
16353 argvec = expand_template_argument_pack (argvec);
16355 len = TREE_VEC_LENGTH (parmvec);
16357 /* Check if the parameters end in a pack, making them
16360 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
16361 parm_variadic_p = 1;
16363 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
16364 return unify_too_few_arguments (explain_p,
16365 TREE_VEC_LENGTH (argvec), len);
16367 for (i = 0; i < len - parm_variadic_p; ++i)
16369 RECUR_AND_CHECK_FAILURE (tparms, targs,
16370 TREE_VEC_ELT (parmvec, i),
16371 TREE_VEC_ELT (argvec, i),
16372 UNIFY_ALLOW_NONE, explain_p);
16375 if (parm_variadic_p
16376 && unify_pack_expansion (tparms, targs,
16379 /*subr=*/true, explain_p))
16382 arg = TYPE_TI_TEMPLATE (arg);
16384 /* Fall through to deduce template name. */
16387 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16388 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16390 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
16392 /* Simple cases: Value already set, does match or doesn't. */
16393 if (targ != NULL_TREE && template_args_equal (targ, arg))
16394 return unify_success (explain_p);
16396 return unify_inconsistency (explain_p, parm, targ, arg);
16400 /* If PARM is `const T' and ARG is only `int', we don't have
16401 a match unless we are allowing additional qualification.
16402 If ARG is `const int' and PARM is just `T' that's OK;
16403 that binds `const int' to `T'. */
16404 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
16406 return unify_cv_qual_mismatch (explain_p, parm, arg);
16408 /* Consider the case where ARG is `const volatile int' and
16409 PARM is `const T'. Then, T should be `volatile int'. */
16410 arg = cp_build_qualified_type_real
16411 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
16412 if (arg == error_mark_node)
16413 return unify_invalid (explain_p);
16415 /* Simple cases: Value already set, does match or doesn't. */
16416 if (targ != NULL_TREE && same_type_p (targ, arg))
16417 return unify_success (explain_p);
16419 return unify_inconsistency (explain_p, parm, targ, arg);
16421 /* Make sure that ARG is not a variable-sized array. (Note
16422 that were talking about variable-sized arrays (like
16423 `int[n]'), rather than arrays of unknown size (like
16424 `int[]').) We'll get very confused by such a type since
16425 the bound of the array is not constant, and therefore
16426 not mangleable. Besides, such types are not allowed in
16427 ISO C++, so we can do as we please here. We do allow
16428 them for 'auto' deduction, since that isn't ABI-exposed. */
16429 if (!is_auto (parm) && variably_modified_type_p (arg, NULL_TREE))
16430 return unify_vla_arg (explain_p, arg);
16432 /* Strip typedefs as in convert_template_argument. */
16433 arg = canonicalize_type_argument (arg, tf_none);
16436 /* If ARG is a parameter pack or an expansion, we cannot unify
16437 against it unless PARM is also a parameter pack. */
16438 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16439 && !template_parameter_pack_p (parm))
16440 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16442 /* If the argument deduction results is a METHOD_TYPE,
16443 then there is a problem.
16444 METHOD_TYPE doesn't map to any real C++ type the result of
16445 the deduction can not be of that type. */
16446 if (TREE_CODE (arg) == METHOD_TYPE)
16447 return unify_method_type_error (explain_p, arg);
16449 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16450 return unify_success (explain_p);
16452 case TEMPLATE_PARM_INDEX:
16453 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16454 if (tparm == error_mark_node)
16455 return unify_invalid (explain_p);
16457 if (TEMPLATE_PARM_LEVEL (parm)
16458 != template_decl_level (tparm))
16460 /* The PARM is not one we're trying to unify. Just check
16461 to see if it matches ARG. */
16462 int result = !(TREE_CODE (arg) == TREE_CODE (parm)
16463 && cp_tree_equal (parm, arg));
16465 unify_expression_unequal (explain_p, parm, arg);
16469 idx = TEMPLATE_PARM_IDX (parm);
16470 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16474 int x = !cp_tree_equal (targ, arg);
16476 unify_inconsistency (explain_p, parm, targ, arg);
16480 /* [temp.deduct.type] If, in the declaration of a function template
16481 with a non-type template-parameter, the non-type
16482 template-parameter is used in an expression in the function
16483 parameter-list and, if the corresponding template-argument is
16484 deduced, the template-argument type shall match the type of the
16485 template-parameter exactly, except that a template-argument
16486 deduced from an array bound may be of any integral type.
16487 The non-type parameter might use already deduced type parameters. */
16488 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
16489 if (!TREE_TYPE (arg))
16490 /* Template-parameter dependent expression. Just accept it for now.
16491 It will later be processed in convert_template_argument. */
16493 else if (same_type_p (TREE_TYPE (arg), tparm))
16495 else if ((strict & UNIFY_ALLOW_INTEGER)
16496 && (TREE_CODE (tparm) == INTEGER_TYPE
16497 || TREE_CODE (tparm) == BOOLEAN_TYPE))
16498 /* Convert the ARG to the type of PARM; the deduced non-type
16499 template argument must exactly match the types of the
16500 corresponding parameter. */
16501 arg = fold (build_nop (tparm, arg));
16502 else if (uses_template_parms (tparm))
16503 /* We haven't deduced the type of this parameter yet. Try again
16505 return unify_success (explain_p);
16507 return unify_type_mismatch (explain_p, tparm, arg);
16509 /* If ARG is a parameter pack or an expansion, we cannot unify
16510 against it unless PARM is also a parameter pack. */
16511 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16512 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
16513 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16515 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16516 return unify_success (explain_p);
16520 /* A pointer-to-member constant can be unified only with
16521 another constant. */
16522 if (TREE_CODE (arg) != PTRMEM_CST)
16523 return unify_ptrmem_cst_mismatch (explain_p, parm, arg);
16525 /* Just unify the class member. It would be useless (and possibly
16526 wrong, depending on the strict flags) to unify also
16527 PTRMEM_CST_CLASS, because we want to be sure that both parm and
16528 arg refer to the same variable, even if through different
16529 classes. For instance:
16531 struct A { int x; };
16534 Unification of &A::x and &B::x must succeed. */
16535 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
16536 PTRMEM_CST_MEMBER (arg), strict, explain_p);
16541 if (TREE_CODE (arg) != POINTER_TYPE)
16542 return unify_type_mismatch (explain_p, parm, arg);
16544 /* [temp.deduct.call]
16546 A can be another pointer or pointer to member type that can
16547 be converted to the deduced A via a qualification
16548 conversion (_conv.qual_).
16550 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
16551 This will allow for additional cv-qualification of the
16552 pointed-to types if appropriate. */
16554 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
16555 /* The derived-to-base conversion only persists through one
16556 level of pointers. */
16557 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
16559 return unify (tparms, targs, TREE_TYPE (parm),
16560 TREE_TYPE (arg), strict, explain_p);
16563 case REFERENCE_TYPE:
16564 if (TREE_CODE (arg) != REFERENCE_TYPE)
16565 return unify_type_mismatch (explain_p, parm, arg);
16566 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16567 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16570 if (TREE_CODE (arg) != ARRAY_TYPE)
16571 return unify_type_mismatch (explain_p, parm, arg);
16572 if ((TYPE_DOMAIN (parm) == NULL_TREE)
16573 != (TYPE_DOMAIN (arg) == NULL_TREE))
16574 return unify_type_mismatch (explain_p, parm, arg);
16575 if (TYPE_DOMAIN (parm) != NULL_TREE)
16582 /* Our representation of array types uses "N - 1" as the
16583 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
16584 not an integer constant. We cannot unify arbitrarily
16585 complex expressions, so we eliminate the MINUS_EXPRs
16587 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
16588 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
16591 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
16592 parm_max = TREE_OPERAND (parm_max, 0);
16594 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
16595 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
16598 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
16599 trying to unify the type of a variable with the type
16600 of a template parameter. For example:
16602 template <unsigned int N>
16603 void f (char (&) [N]);
16610 Here, the type of the ARG will be "int [g(i)]", and
16611 may be a SAVE_EXPR, etc. */
16612 if (TREE_CODE (arg_max) != MINUS_EXPR)
16613 return unify_vla_arg (explain_p, arg);
16614 arg_max = TREE_OPERAND (arg_max, 0);
16617 /* If only one of the bounds used a MINUS_EXPR, compensate
16618 by adding one to the other bound. */
16619 if (parm_cst && !arg_cst)
16620 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
16624 else if (arg_cst && !parm_cst)
16625 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
16630 RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max,
16631 UNIFY_ALLOW_INTEGER, explain_p);
16633 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16634 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16641 case ENUMERAL_TYPE:
16644 if (TREE_CODE (arg) != TREE_CODE (parm))
16645 return unify_type_mismatch (explain_p, parm, arg);
16647 /* We have already checked cv-qualification at the top of the
16649 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
16650 return unify_type_mismatch (explain_p, parm, arg);
16652 /* As far as unification is concerned, this wins. Later checks
16653 will invalidate it if necessary. */
16654 return unify_success (explain_p);
16656 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
16657 /* Type INTEGER_CST can come from ordinary constant template args. */
16659 while (TREE_CODE (arg) == NOP_EXPR)
16660 arg = TREE_OPERAND (arg, 0);
16662 if (TREE_CODE (arg) != INTEGER_CST)
16663 return unify_template_argument_mismatch (explain_p, parm, arg);
16664 return (tree_int_cst_equal (parm, arg)
16665 ? unify_success (explain_p)
16666 : unify_template_argument_mismatch (explain_p, parm, arg));
16670 int i, len, argslen;
16671 int parm_variadic_p = 0;
16673 if (TREE_CODE (arg) != TREE_VEC)
16674 return unify_template_argument_mismatch (explain_p, parm, arg);
16676 len = TREE_VEC_LENGTH (parm);
16677 argslen = TREE_VEC_LENGTH (arg);
16679 /* Check for pack expansions in the parameters. */
16680 for (i = 0; i < len; ++i)
16682 if (PACK_EXPANSION_P (TREE_VEC_ELT (parm, i)))
16685 /* We can unify against something with a trailing
16687 parm_variadic_p = 1;
16689 /* [temp.deduct.type]/9: If the template argument list of
16690 P contains a pack expansion that is not the last
16691 template argument, the entire template argument list
16692 is a non-deduced context. */
16693 return unify_success (explain_p);
16697 /* If we don't have enough arguments to satisfy the parameters
16698 (not counting the pack expression at the end), or we have
16699 too many arguments for a parameter list that doesn't end in
16700 a pack expression, we can't unify. */
16701 if (parm_variadic_p
16702 ? argslen < len - parm_variadic_p
16704 return unify_arity (explain_p, TREE_VEC_LENGTH (arg), len);
16706 /* Unify all of the parameters that precede the (optional)
16707 pack expression. */
16708 for (i = 0; i < len - parm_variadic_p; ++i)
16710 RECUR_AND_CHECK_FAILURE (tparms, targs,
16711 TREE_VEC_ELT (parm, i),
16712 TREE_VEC_ELT (arg, i),
16713 UNIFY_ALLOW_NONE, explain_p);
16715 if (parm_variadic_p)
16716 return unify_pack_expansion (tparms, targs, parm, arg,
16718 /*subr=*/true, explain_p);
16719 return unify_success (explain_p);
16724 if (TREE_CODE (arg) != TREE_CODE (parm))
16725 return unify_type_mismatch (explain_p, parm, arg);
16727 if (TYPE_PTRMEMFUNC_P (parm))
16729 if (!TYPE_PTRMEMFUNC_P (arg))
16730 return unify_type_mismatch (explain_p, parm, arg);
16732 return unify (tparms, targs,
16733 TYPE_PTRMEMFUNC_FN_TYPE (parm),
16734 TYPE_PTRMEMFUNC_FN_TYPE (arg),
16735 strict, explain_p);
16738 if (CLASSTYPE_TEMPLATE_INFO (parm))
16740 tree t = NULL_TREE;
16742 if (strict_in & UNIFY_ALLOW_DERIVED)
16744 /* First, we try to unify the PARM and ARG directly. */
16745 t = try_class_unification (tparms, targs,
16746 parm, arg, explain_p);
16750 /* Fallback to the special case allowed in
16751 [temp.deduct.call]:
16753 If P is a class, and P has the form
16754 template-id, then A can be a derived class of
16755 the deduced A. Likewise, if P is a pointer to
16756 a class of the form template-id, A can be a
16757 pointer to a derived class pointed to by the
16759 enum template_base_result r;
16760 r = get_template_base (tparms, targs, parm, arg,
16764 return unify_no_common_base (explain_p, r, parm, arg);
16767 else if (CLASSTYPE_TEMPLATE_INFO (arg)
16768 && (CLASSTYPE_TI_TEMPLATE (parm)
16769 == CLASSTYPE_TI_TEMPLATE (arg)))
16770 /* Perhaps PARM is something like S<U> and ARG is S<int>.
16771 Then, we should unify `int' and `U'. */
16774 /* There's no chance of unification succeeding. */
16775 return unify_type_mismatch (explain_p, parm, arg);
16777 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
16778 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explain_p);
16780 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
16781 return unify_type_mismatch (explain_p, parm, arg);
16782 return unify_success (explain_p);
16785 case FUNCTION_TYPE:
16787 unsigned int nargs;
16792 if (TREE_CODE (arg) != TREE_CODE (parm))
16793 return unify_type_mismatch (explain_p, parm, arg);
16795 /* CV qualifications for methods can never be deduced, they must
16796 match exactly. We need to check them explicitly here,
16797 because type_unification_real treats them as any other
16798 cv-qualified parameter. */
16799 if (TREE_CODE (parm) == METHOD_TYPE
16800 && (!check_cv_quals_for_unify
16802 class_of_this_parm (arg),
16803 class_of_this_parm (parm))))
16804 return unify_cv_qual_mismatch (explain_p, parm, arg);
16806 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm),
16807 TREE_TYPE (arg), UNIFY_ALLOW_NONE, explain_p);
16809 nargs = list_length (TYPE_ARG_TYPES (arg));
16810 args = XALLOCAVEC (tree, nargs);
16811 for (a = TYPE_ARG_TYPES (arg), i = 0;
16812 a != NULL_TREE && a != void_list_node;
16813 a = TREE_CHAIN (a), ++i)
16814 args[i] = TREE_VALUE (a);
16817 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
16818 args, nargs, 1, DEDUCE_EXACT,
16819 LOOKUP_NORMAL, explain_p);
16823 /* Unify a pointer to member with a pointer to member function, which
16824 deduces the type of the member as a function type. */
16825 if (TYPE_PTRMEMFUNC_P (arg))
16830 /* Check top-level cv qualifiers */
16831 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
16832 return unify_cv_qual_mismatch (explain_p, parm, arg);
16834 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16835 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg),
16836 UNIFY_ALLOW_NONE, explain_p);
16838 /* Determine the type of the function we are unifying against. */
16839 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
16841 build_function_type (TREE_TYPE (method_type),
16842 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
16844 /* Extract the cv-qualifiers of the member function from the
16845 implicit object parameter and place them on the function
16846 type to be restored later. */
16847 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
16848 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict, explain_p);
16851 if (TREE_CODE (arg) != OFFSET_TYPE)
16852 return unify_type_mismatch (explain_p, parm, arg);
16853 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16854 TYPE_OFFSET_BASETYPE (arg),
16855 UNIFY_ALLOW_NONE, explain_p);
16856 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16857 strict, explain_p);
16860 if (DECL_TEMPLATE_PARM_P (parm))
16861 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict, explain_p);
16862 if (arg != integral_constant_value (parm))
16863 return unify_template_argument_mismatch (explain_p, parm, arg);
16864 return unify_success (explain_p);
16867 case TEMPLATE_DECL:
16868 /* Matched cases are handled by the ARG == PARM test above. */
16869 return unify_template_argument_mismatch (explain_p, parm, arg);
16872 /* A non-type template parameter that is a variable should be a
16873 an integral constant, in which case, it whould have been
16874 folded into its (constant) value. So we should not be getting
16875 a variable here. */
16876 gcc_unreachable ();
16878 case TYPE_ARGUMENT_PACK:
16879 case NONTYPE_ARGUMENT_PACK:
16880 return unify (tparms, targs, ARGUMENT_PACK_ARGS (parm),
16881 ARGUMENT_PACK_ARGS (arg), strict, explain_p);
16884 case DECLTYPE_TYPE:
16885 case UNDERLYING_TYPE:
16886 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
16887 or UNDERLYING_TYPE nodes. */
16888 return unify_success (explain_p);
16891 /* Unification fails if we hit an error node. */
16892 return unify_invalid (explain_p);
16895 /* An unresolved overload is a nondeduced context. */
16896 if (is_overloaded_fn (parm) || type_unknown_p (parm))
16897 return unify_success (explain_p);
16898 gcc_assert (EXPR_P (parm));
16900 /* We must be looking at an expression. This can happen with
16904 void foo(S<I>, S<I + 2>);
16906 This is a "nondeduced context":
16910 The nondeduced contexts are:
16912 --A type that is a template-id in which one or more of
16913 the template-arguments is an expression that references
16914 a template-parameter.
16916 In these cases, we assume deduction succeeded, but don't
16917 actually infer any unifications. */
16919 if (!uses_template_parms (parm)
16920 && !template_args_equal (parm, arg))
16921 return unify_expression_unequal (explain_p, parm, arg);
16923 return unify_success (explain_p);
16926 #undef RECUR_AND_CHECK_FAILURE
16928 /* Note that DECL can be defined in this translation unit, if
16932 mark_definable (tree decl)
16935 DECL_NOT_REALLY_EXTERN (decl) = 1;
16936 FOR_EACH_CLONE (clone, decl)
16937 DECL_NOT_REALLY_EXTERN (clone) = 1;
16940 /* Called if RESULT is explicitly instantiated, or is a member of an
16941 explicitly instantiated class. */
16944 mark_decl_instantiated (tree result, int extern_p)
16946 SET_DECL_EXPLICIT_INSTANTIATION (result);
16948 /* If this entity has already been written out, it's too late to
16949 make any modifications. */
16950 if (TREE_ASM_WRITTEN (result))
16953 if (TREE_CODE (result) != FUNCTION_DECL)
16954 /* The TREE_PUBLIC flag for function declarations will have been
16955 set correctly by tsubst. */
16956 TREE_PUBLIC (result) = 1;
16958 /* This might have been set by an earlier implicit instantiation. */
16959 DECL_COMDAT (result) = 0;
16962 DECL_NOT_REALLY_EXTERN (result) = 0;
16965 mark_definable (result);
16966 /* Always make artificials weak. */
16967 if (DECL_ARTIFICIAL (result) && flag_weak)
16968 comdat_linkage (result);
16969 /* For WIN32 we also want to put explicit instantiations in
16970 linkonce sections. */
16971 else if (TREE_PUBLIC (result))
16972 maybe_make_one_only (result);
16975 /* If EXTERN_P, then this function will not be emitted -- unless
16976 followed by an explicit instantiation, at which point its linkage
16977 will be adjusted. If !EXTERN_P, then this function will be
16978 emitted here. In neither circumstance do we want
16979 import_export_decl to adjust the linkage. */
16980 DECL_INTERFACE_KNOWN (result) = 1;
16983 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
16984 important template arguments. If any are missing, we check whether
16985 they're important by using error_mark_node for substituting into any
16986 args that were used for partial ordering (the ones between ARGS and END)
16987 and seeing if it bubbles up. */
16990 check_undeduced_parms (tree targs, tree args, tree end)
16992 bool found = false;
16994 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
16995 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
16998 TREE_VEC_ELT (targs, i) = error_mark_node;
17002 for (; args != end; args = TREE_CHAIN (args))
17004 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
17005 if (substed == error_mark_node)
17012 /* Given two function templates PAT1 and PAT2, return:
17014 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
17015 -1 if PAT2 is more specialized than PAT1.
17016 0 if neither is more specialized.
17018 LEN indicates the number of parameters we should consider
17019 (defaulted parameters should not be considered).
17021 The 1998 std underspecified function template partial ordering, and
17022 DR214 addresses the issue. We take pairs of arguments, one from
17023 each of the templates, and deduce them against each other. One of
17024 the templates will be more specialized if all the *other*
17025 template's arguments deduce against its arguments and at least one
17026 of its arguments *does* *not* deduce against the other template's
17027 corresponding argument. Deduction is done as for class templates.
17028 The arguments used in deduction have reference and top level cv
17029 qualifiers removed. Iff both arguments were originally reference
17030 types *and* deduction succeeds in both directions, the template
17031 with the more cv-qualified argument wins for that pairing (if
17032 neither is more cv-qualified, they both are equal). Unlike regular
17033 deduction, after all the arguments have been deduced in this way,
17034 we do *not* verify the deduced template argument values can be
17035 substituted into non-deduced contexts.
17037 The logic can be a bit confusing here, because we look at deduce1 and
17038 targs1 to see if pat2 is at least as specialized, and vice versa; if we
17039 can find template arguments for pat1 to make arg1 look like arg2, that
17040 means that arg2 is at least as specialized as arg1. */
17043 more_specialized_fn (tree pat1, tree pat2, int len)
17045 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
17046 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
17047 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
17048 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
17049 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
17050 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
17051 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
17052 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
17053 tree origs1, origs2;
17054 bool lose1 = false;
17055 bool lose2 = false;
17057 /* Remove the this parameter from non-static member functions. If
17058 one is a non-static member function and the other is not a static
17059 member function, remove the first parameter from that function
17060 also. This situation occurs for operator functions where we
17061 locate both a member function (with this pointer) and non-member
17062 operator (with explicit first operand). */
17063 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
17065 len--; /* LEN is the number of significant arguments for DECL1 */
17066 args1 = TREE_CHAIN (args1);
17067 if (!DECL_STATIC_FUNCTION_P (decl2))
17068 args2 = TREE_CHAIN (args2);
17070 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
17072 args2 = TREE_CHAIN (args2);
17073 if (!DECL_STATIC_FUNCTION_P (decl1))
17076 args1 = TREE_CHAIN (args1);
17080 /* If only one is a conversion operator, they are unordered. */
17081 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
17084 /* Consider the return type for a conversion function */
17085 if (DECL_CONV_FN_P (decl1))
17087 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
17088 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
17092 processing_template_decl++;
17098 /* Stop when an ellipsis is seen. */
17099 && args1 != NULL_TREE && args2 != NULL_TREE)
17101 tree arg1 = TREE_VALUE (args1);
17102 tree arg2 = TREE_VALUE (args2);
17103 int deduce1, deduce2;
17107 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17108 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17110 /* When both arguments are pack expansions, we need only
17111 unify the patterns themselves. */
17112 arg1 = PACK_EXPANSION_PATTERN (arg1);
17113 arg2 = PACK_EXPANSION_PATTERN (arg2);
17115 /* This is the last comparison we need to do. */
17119 if (TREE_CODE (arg1) == REFERENCE_TYPE)
17121 arg1 = TREE_TYPE (arg1);
17122 quals1 = cp_type_quals (arg1);
17125 if (TREE_CODE (arg2) == REFERENCE_TYPE)
17127 arg2 = TREE_TYPE (arg2);
17128 quals2 = cp_type_quals (arg2);
17131 if ((quals1 < 0) != (quals2 < 0))
17133 /* Only of the args is a reference, see if we should apply
17134 array/function pointer decay to it. This is not part of
17135 DR214, but is, IMHO, consistent with the deduction rules
17136 for the function call itself, and with our earlier
17137 implementation of the underspecified partial ordering
17138 rules. (nathan). */
17141 switch (TREE_CODE (arg1))
17144 arg1 = TREE_TYPE (arg1);
17146 case FUNCTION_TYPE:
17147 arg1 = build_pointer_type (arg1);
17156 switch (TREE_CODE (arg2))
17159 arg2 = TREE_TYPE (arg2);
17161 case FUNCTION_TYPE:
17162 arg2 = build_pointer_type (arg2);
17171 arg1 = TYPE_MAIN_VARIANT (arg1);
17172 arg2 = TYPE_MAIN_VARIANT (arg2);
17174 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
17176 int i, len2 = list_length (args2);
17177 tree parmvec = make_tree_vec (1);
17178 tree argvec = make_tree_vec (len2);
17181 /* Setup the parameter vector, which contains only ARG1. */
17182 TREE_VEC_ELT (parmvec, 0) = arg1;
17184 /* Setup the argument vector, which contains the remaining
17186 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
17187 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17189 deduce1 = (unify_pack_expansion (tparms1, targs1, parmvec,
17190 argvec, DEDUCE_EXACT,
17191 /*subr=*/true, /*explain_p=*/false)
17194 /* We cannot deduce in the other direction, because ARG1 is
17195 a pack expansion but ARG2 is not. */
17198 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17200 int i, len1 = list_length (args1);
17201 tree parmvec = make_tree_vec (1);
17202 tree argvec = make_tree_vec (len1);
17205 /* Setup the parameter vector, which contains only ARG1. */
17206 TREE_VEC_ELT (parmvec, 0) = arg2;
17208 /* Setup the argument vector, which contains the remaining
17210 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
17211 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17213 deduce2 = (unify_pack_expansion (tparms2, targs2, parmvec,
17214 argvec, DEDUCE_EXACT,
17215 /*subr=*/true, /*explain_p=*/false)
17218 /* We cannot deduce in the other direction, because ARG2 is
17219 a pack expansion but ARG1 is not.*/
17225 /* The normal case, where neither argument is a pack
17227 deduce1 = (unify (tparms1, targs1, arg1, arg2,
17228 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17230 deduce2 = (unify (tparms2, targs2, arg2, arg1,
17231 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17235 /* If we couldn't deduce arguments for tparms1 to make arg1 match
17236 arg2, then arg2 is not as specialized as arg1. */
17242 /* "If, for a given type, deduction succeeds in both directions
17243 (i.e., the types are identical after the transformations above)
17244 and if the type from the argument template is more cv-qualified
17245 than the type from the parameter template (as described above)
17246 that type is considered to be more specialized than the other. If
17247 neither type is more cv-qualified than the other then neither type
17248 is more specialized than the other." */
17250 if (deduce1 && deduce2
17251 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
17253 if ((quals1 & quals2) == quals2)
17255 if ((quals1 & quals2) == quals1)
17259 if (lose1 && lose2)
17260 /* We've failed to deduce something in either direction.
17261 These must be unordered. */
17264 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17265 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17266 /* We have already processed all of the arguments in our
17267 handing of the pack expansion type. */
17270 args1 = TREE_CHAIN (args1);
17271 args2 = TREE_CHAIN (args2);
17274 /* "In most cases, all template parameters must have values in order for
17275 deduction to succeed, but for partial ordering purposes a template
17276 parameter may remain without a value provided it is not used in the
17277 types being used for partial ordering."
17279 Thus, if we are missing any of the targs1 we need to substitute into
17280 origs1, then pat2 is not as specialized as pat1. This can happen when
17281 there is a nondeduced context. */
17282 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
17284 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
17287 processing_template_decl--;
17289 /* All things being equal, if the next argument is a pack expansion
17290 for one function but not for the other, prefer the
17291 non-variadic function. FIXME this is bogus; see c++/41958. */
17293 && args1 && TREE_VALUE (args1)
17294 && args2 && TREE_VALUE (args2))
17296 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
17297 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
17300 if (lose1 == lose2)
17308 /* Determine which of two partial specializations is more specialized.
17310 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
17311 to the first partial specialization. The TREE_VALUE is the
17312 innermost set of template parameters for the partial
17313 specialization. PAT2 is similar, but for the second template.
17315 Return 1 if the first partial specialization is more specialized;
17316 -1 if the second is more specialized; 0 if neither is more
17319 See [temp.class.order] for information about determining which of
17320 two templates is more specialized. */
17323 more_specialized_class (tree pat1, tree pat2)
17328 bool any_deductions = false;
17330 tmpl1 = TREE_TYPE (pat1);
17331 tmpl2 = TREE_TYPE (pat2);
17333 /* Just like what happens for functions, if we are ordering between
17334 different class template specializations, we may encounter dependent
17335 types in the arguments, and we need our dependency check functions
17336 to behave correctly. */
17337 ++processing_template_decl;
17338 targs = get_class_bindings (TREE_VALUE (pat1),
17339 CLASSTYPE_TI_ARGS (tmpl1),
17340 CLASSTYPE_TI_ARGS (tmpl2));
17344 any_deductions = true;
17347 targs = get_class_bindings (TREE_VALUE (pat2),
17348 CLASSTYPE_TI_ARGS (tmpl2),
17349 CLASSTYPE_TI_ARGS (tmpl1));
17353 any_deductions = true;
17355 --processing_template_decl;
17357 /* In the case of a tie where at least one of the class templates
17358 has a parameter pack at the end, the template with the most
17359 non-packed parameters wins. */
17362 && (template_args_variadic_p (TREE_PURPOSE (pat1))
17363 || template_args_variadic_p (TREE_PURPOSE (pat2))))
17365 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
17366 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
17367 int len1 = TREE_VEC_LENGTH (args1);
17368 int len2 = TREE_VEC_LENGTH (args2);
17370 /* We don't count the pack expansion at the end. */
17371 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
17373 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
17378 else if (len1 < len2)
17385 /* Return the template arguments that will produce the function signature
17386 DECL from the function template FN, with the explicit template
17387 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
17388 also match. Return NULL_TREE if no satisfactory arguments could be
17392 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
17394 int ntparms = DECL_NTPARMS (fn);
17395 tree targs = make_tree_vec (ntparms);
17397 tree decl_arg_types;
17399 unsigned int nargs, ix;
17402 /* Substitute the explicit template arguments into the type of DECL.
17403 The call to fn_type_unification will handle substitution into the
17405 decl_type = TREE_TYPE (decl);
17406 if (explicit_args && uses_template_parms (decl_type))
17409 tree converted_args;
17411 if (DECL_TEMPLATE_INFO (decl))
17412 tmpl = DECL_TI_TEMPLATE (decl);
17414 /* We can get here for some invalid specializations. */
17418 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17419 explicit_args, NULL_TREE,
17421 /*require_all_args=*/false,
17422 /*use_default_args=*/false);
17423 if (converted_args == error_mark_node)
17426 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
17427 if (decl_type == error_mark_node)
17431 /* Never do unification on the 'this' parameter. */
17432 decl_arg_types = skip_artificial_parms_for (decl,
17433 TYPE_ARG_TYPES (decl_type));
17435 nargs = list_length (decl_arg_types);
17436 args = XALLOCAVEC (tree, nargs);
17437 for (arg = decl_arg_types, ix = 0;
17438 arg != NULL_TREE && arg != void_list_node;
17439 arg = TREE_CHAIN (arg), ++ix)
17440 args[ix] = TREE_VALUE (arg);
17442 if (fn_type_unification (fn, explicit_args, targs,
17444 (check_rettype || DECL_CONV_FN_P (fn)
17445 ? TREE_TYPE (decl_type) : NULL_TREE),
17446 DEDUCE_EXACT, LOOKUP_NORMAL, /*explain_p=*/false))
17452 /* Return the innermost template arguments that, when applied to a
17453 template specialization whose innermost template parameters are
17454 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
17457 For example, suppose we have:
17459 template <class T, class U> struct S {};
17460 template <class T> struct S<T*, int> {};
17462 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
17463 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
17464 int}. The resulting vector will be {double}, indicating that `T'
17465 is bound to `double'. */
17468 get_class_bindings (tree tparms, tree spec_args, tree args)
17470 int i, ntparms = TREE_VEC_LENGTH (tparms);
17472 tree innermost_deduced_args;
17474 innermost_deduced_args = make_tree_vec (ntparms);
17475 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17477 deduced_args = copy_node (args);
17478 SET_TMPL_ARGS_LEVEL (deduced_args,
17479 TMPL_ARGS_DEPTH (deduced_args),
17480 innermost_deduced_args);
17483 deduced_args = innermost_deduced_args;
17485 if (unify (tparms, deduced_args,
17486 INNERMOST_TEMPLATE_ARGS (spec_args),
17487 INNERMOST_TEMPLATE_ARGS (args),
17488 UNIFY_ALLOW_NONE, /*explain_p=*/false))
17491 for (i = 0; i < ntparms; ++i)
17492 if (! TREE_VEC_ELT (innermost_deduced_args, i))
17495 /* Verify that nondeduced template arguments agree with the type
17496 obtained from argument deduction.
17500 struct A { typedef int X; };
17501 template <class T, class U> struct C {};
17502 template <class T> struct C<T, typename T::X> {};
17504 Then with the instantiation `C<A, int>', we can deduce that
17505 `T' is `A' but unify () does not check whether `typename T::X'
17507 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
17508 if (spec_args == error_mark_node
17509 /* We only need to check the innermost arguments; the other
17510 arguments will always agree. */
17511 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
17512 INNERMOST_TEMPLATE_ARGS (args)))
17515 /* Now that we have bindings for all of the template arguments,
17516 ensure that the arguments deduced for the template template
17517 parameters have compatible template parameter lists. See the use
17518 of template_template_parm_bindings_ok_p in fn_type_unification
17519 for more information. */
17520 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
17523 return deduced_args;
17526 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
17527 Return the TREE_LIST node with the most specialized template, if
17528 any. If there is no most specialized template, the error_mark_node
17531 Note that this function does not look at, or modify, the
17532 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
17533 returned is one of the elements of INSTANTIATIONS, callers may
17534 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
17535 and retrieve it from the value returned. */
17538 most_specialized_instantiation (tree templates)
17542 ++processing_template_decl;
17545 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
17549 if (get_bindings (TREE_VALUE (champ),
17550 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17551 NULL_TREE, /*check_ret=*/true))
17554 if (get_bindings (TREE_VALUE (fn),
17555 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17556 NULL_TREE, /*check_ret=*/true))
17563 /* Equally specialized, move to next function. If there
17564 is no next function, nothing's most specialized. */
17565 fn = TREE_CHAIN (fn);
17573 /* Now verify that champ is better than everything earlier in the
17574 instantiation list. */
17575 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
17576 if (get_bindings (TREE_VALUE (champ),
17577 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17578 NULL_TREE, /*check_ret=*/true)
17579 || !get_bindings (TREE_VALUE (fn),
17580 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17581 NULL_TREE, /*check_ret=*/true))
17587 processing_template_decl--;
17590 return error_mark_node;
17595 /* If DECL is a specialization of some template, return the most
17596 general such template. Otherwise, returns NULL_TREE.
17598 For example, given:
17600 template <class T> struct S { template <class U> void f(U); };
17602 if TMPL is `template <class U> void S<int>::f(U)' this will return
17603 the full template. This function will not trace past partial
17604 specializations, however. For example, given in addition:
17606 template <class T> struct S<T*> { template <class U> void f(U); };
17608 if TMPL is `template <class U> void S<int*>::f(U)' this will return
17609 `template <class T> template <class U> S<T*>::f(U)'. */
17612 most_general_template (tree decl)
17614 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
17615 an immediate specialization. */
17616 if (TREE_CODE (decl) == FUNCTION_DECL)
17618 if (DECL_TEMPLATE_INFO (decl)) {
17619 decl = DECL_TI_TEMPLATE (decl);
17621 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
17622 template friend. */
17623 if (TREE_CODE (decl) != TEMPLATE_DECL)
17629 /* Look for more and more general templates. */
17630 while (DECL_TEMPLATE_INFO (decl))
17632 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
17633 (See cp-tree.h for details.) */
17634 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
17637 if (CLASS_TYPE_P (TREE_TYPE (decl))
17638 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
17641 /* Stop if we run into an explicitly specialized class template. */
17642 if (!DECL_NAMESPACE_SCOPE_P (decl)
17643 && DECL_CONTEXT (decl)
17644 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
17647 decl = DECL_TI_TEMPLATE (decl);
17653 /* Return the most specialized of the class template partial
17654 specializations of TMPL which can produce TYPE, a specialization of
17655 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
17656 a _TYPE node corresponding to the partial specialization, while the
17657 TREE_PURPOSE is the set of template arguments that must be
17658 substituted into the TREE_TYPE in order to generate TYPE.
17660 If the choice of partial specialization is ambiguous, a diagnostic
17661 is issued, and the error_mark_node is returned. If there are no
17662 partial specializations of TMPL matching TYPE, then NULL_TREE is
17666 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
17668 tree list = NULL_TREE;
17674 tree outer_args = NULL_TREE;
17676 tmpl = most_general_template (tmpl);
17677 args = CLASSTYPE_TI_ARGS (type);
17679 /* For determining which partial specialization to use, only the
17680 innermost args are interesting. */
17681 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17683 outer_args = strip_innermost_template_args (args, 1);
17684 args = INNERMOST_TEMPLATE_ARGS (args);
17687 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
17689 tree partial_spec_args;
17691 tree parms = TREE_VALUE (t);
17693 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
17695 ++processing_template_decl;
17701 /* Discard the outer levels of args, and then substitute in the
17702 template args from the enclosing class. */
17703 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
17704 partial_spec_args = tsubst_template_args
17705 (partial_spec_args, outer_args, tf_none, NULL_TREE);
17707 /* PARMS already refers to just the innermost parms, but the
17708 template parms in partial_spec_args had their levels lowered
17709 by tsubst, so we need to do the same for the parm list. We
17710 can't just tsubst the TREE_VEC itself, as tsubst wants to
17711 treat a TREE_VEC as an argument vector. */
17712 parms = copy_node (parms);
17713 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
17714 TREE_VEC_ELT (parms, i) =
17715 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
17719 partial_spec_args =
17720 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17721 add_to_template_args (outer_args,
17722 partial_spec_args),
17724 /*require_all_args=*/true,
17725 /*use_default_args=*/true);
17727 --processing_template_decl;
17729 if (partial_spec_args == error_mark_node)
17730 return error_mark_node;
17732 spec_args = get_class_bindings (parms,
17738 spec_args = add_to_template_args (outer_args, spec_args);
17739 list = tree_cons (spec_args, TREE_VALUE (t), list);
17740 TREE_TYPE (list) = TREE_TYPE (t);
17747 ambiguous_p = false;
17750 t = TREE_CHAIN (t);
17751 for (; t; t = TREE_CHAIN (t))
17753 fate = more_specialized_class (champ, t);
17760 t = TREE_CHAIN (t);
17763 ambiguous_p = true;
17772 for (t = list; t && t != champ; t = TREE_CHAIN (t))
17774 fate = more_specialized_class (champ, t);
17777 ambiguous_p = true;
17785 char *spaces = NULL;
17786 if (!(complain & tf_error))
17787 return error_mark_node;
17788 error ("ambiguous class template instantiation for %q#T", type);
17789 str = ngettext ("candidate is:", "candidates are:", list_length (list));
17790 for (t = list; t; t = TREE_CHAIN (t))
17792 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
17793 spaces = spaces ? spaces : get_spaces (str);
17796 return error_mark_node;
17802 /* Explicitly instantiate DECL. */
17805 do_decl_instantiation (tree decl, tree storage)
17807 tree result = NULL_TREE;
17810 if (!decl || decl == error_mark_node)
17811 /* An error occurred, for which grokdeclarator has already issued
17812 an appropriate message. */
17814 else if (! DECL_LANG_SPECIFIC (decl))
17816 error ("explicit instantiation of non-template %q#D", decl);
17819 else if (TREE_CODE (decl) == VAR_DECL)
17821 /* There is an asymmetry here in the way VAR_DECLs and
17822 FUNCTION_DECLs are handled by grokdeclarator. In the case of
17823 the latter, the DECL we get back will be marked as a
17824 template instantiation, and the appropriate
17825 DECL_TEMPLATE_INFO will be set up. This does not happen for
17826 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
17827 should handle VAR_DECLs as it currently handles
17829 if (!DECL_CLASS_SCOPE_P (decl))
17831 error ("%qD is not a static data member of a class template", decl);
17834 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
17835 if (!result || TREE_CODE (result) != VAR_DECL)
17837 error ("no matching template for %qD found", decl);
17840 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
17842 error ("type %qT for explicit instantiation %qD does not match "
17843 "declared type %qT", TREE_TYPE (result), decl,
17848 else if (TREE_CODE (decl) != FUNCTION_DECL)
17850 error ("explicit instantiation of %q#D", decl);
17856 /* Check for various error cases. Note that if the explicit
17857 instantiation is valid the RESULT will currently be marked as an
17858 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
17859 until we get here. */
17861 if (DECL_TEMPLATE_SPECIALIZATION (result))
17863 /* DR 259 [temp.spec].
17865 Both an explicit instantiation and a declaration of an explicit
17866 specialization shall not appear in a program unless the explicit
17867 instantiation follows a declaration of the explicit specialization.
17869 For a given set of template parameters, if an explicit
17870 instantiation of a template appears after a declaration of an
17871 explicit specialization for that template, the explicit
17872 instantiation has no effect. */
17875 else if (DECL_EXPLICIT_INSTANTIATION (result))
17879 No program shall explicitly instantiate any template more
17882 We check DECL_NOT_REALLY_EXTERN so as not to complain when
17883 the first instantiation was `extern' and the second is not,
17884 and EXTERN_P for the opposite case. */
17885 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
17886 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
17887 /* If an "extern" explicit instantiation follows an ordinary
17888 explicit instantiation, the template is instantiated. */
17892 else if (!DECL_IMPLICIT_INSTANTIATION (result))
17894 error ("no matching template for %qD found", result);
17897 else if (!DECL_TEMPLATE_INFO (result))
17899 permerror (input_location, "explicit instantiation of non-template %q#D", result);
17903 if (storage == NULL_TREE)
17905 else if (storage == ridpointers[(int) RID_EXTERN])
17907 if (!in_system_header && (cxx_dialect == cxx98))
17908 pedwarn (input_location, OPT_pedantic,
17909 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
17914 error ("storage class %qD applied to template instantiation", storage);
17916 check_explicit_instantiation_namespace (result);
17917 mark_decl_instantiated (result, extern_p);
17919 instantiate_decl (result, /*defer_ok=*/1,
17920 /*expl_inst_class_mem_p=*/false);
17924 mark_class_instantiated (tree t, int extern_p)
17926 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
17927 SET_CLASSTYPE_INTERFACE_KNOWN (t);
17928 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
17929 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
17932 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
17933 rest_of_type_compilation (t, 1);
17937 /* Called from do_type_instantiation through binding_table_foreach to
17938 do recursive instantiation for the type bound in ENTRY. */
17940 bt_instantiate_type_proc (binding_entry entry, void *data)
17942 tree storage = *(tree *) data;
17944 if (MAYBE_CLASS_TYPE_P (entry->type)
17945 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
17946 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
17949 /* Called from do_type_instantiation to instantiate a member
17950 (a member function or a static member variable) of an
17951 explicitly instantiated class template. */
17953 instantiate_class_member (tree decl, int extern_p)
17955 mark_decl_instantiated (decl, extern_p);
17957 instantiate_decl (decl, /*defer_ok=*/1,
17958 /*expl_inst_class_mem_p=*/true);
17961 /* Perform an explicit instantiation of template class T. STORAGE, if
17962 non-null, is the RID for extern, inline or static. COMPLAIN is
17963 nonzero if this is called from the parser, zero if called recursively,
17964 since the standard is unclear (as detailed below). */
17967 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
17972 int previous_instantiation_extern_p = 0;
17974 if (TREE_CODE (t) == TYPE_DECL)
17977 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
17980 (TYPE_TEMPLATE_INFO (t)) ? TYPE_TI_TEMPLATE (t) : NULL;
17982 error ("explicit instantiation of non-class template %qD", tmpl);
17984 error ("explicit instantiation of non-template type %qT", t);
17990 if (!COMPLETE_TYPE_P (t))
17992 if (complain & tf_error)
17993 error ("explicit instantiation of %q#T before definition of template",
17998 if (storage != NULL_TREE)
18000 if (!in_system_header)
18002 if (storage == ridpointers[(int) RID_EXTERN])
18004 if (cxx_dialect == cxx98)
18005 pedwarn (input_location, OPT_pedantic,
18006 "ISO C++ 1998 forbids the use of %<extern%> on "
18007 "explicit instantiations");
18010 pedwarn (input_location, OPT_pedantic,
18011 "ISO C++ forbids the use of %qE"
18012 " on explicit instantiations", storage);
18015 if (storage == ridpointers[(int) RID_INLINE])
18017 else if (storage == ridpointers[(int) RID_EXTERN])
18019 else if (storage == ridpointers[(int) RID_STATIC])
18023 error ("storage class %qD applied to template instantiation",
18029 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
18031 /* DR 259 [temp.spec].
18033 Both an explicit instantiation and a declaration of an explicit
18034 specialization shall not appear in a program unless the explicit
18035 instantiation follows a declaration of the explicit specialization.
18037 For a given set of template parameters, if an explicit
18038 instantiation of a template appears after a declaration of an
18039 explicit specialization for that template, the explicit
18040 instantiation has no effect. */
18043 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
18047 No program shall explicitly instantiate any template more
18050 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
18051 instantiation was `extern'. If EXTERN_P then the second is.
18052 These cases are OK. */
18053 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
18055 if (!previous_instantiation_extern_p && !extern_p
18056 && (complain & tf_error))
18057 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
18059 /* If we've already instantiated the template, just return now. */
18060 if (!CLASSTYPE_INTERFACE_ONLY (t))
18064 check_explicit_instantiation_namespace (TYPE_NAME (t));
18065 mark_class_instantiated (t, extern_p);
18073 /* In contrast to implicit instantiation, where only the
18074 declarations, and not the definitions, of members are
18075 instantiated, we have here:
18079 The explicit instantiation of a class template specialization
18080 implies the instantiation of all of its members not
18081 previously explicitly specialized in the translation unit
18082 containing the explicit instantiation.
18084 Of course, we can't instantiate member template classes, since
18085 we don't have any arguments for them. Note that the standard
18086 is unclear on whether the instantiation of the members are
18087 *explicit* instantiations or not. However, the most natural
18088 interpretation is that it should be an explicit instantiation. */
18091 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
18092 if (TREE_CODE (tmp) == FUNCTION_DECL
18093 && DECL_TEMPLATE_INSTANTIATION (tmp))
18094 instantiate_class_member (tmp, extern_p);
18096 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
18097 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
18098 instantiate_class_member (tmp, extern_p);
18100 if (CLASSTYPE_NESTED_UTDS (t))
18101 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
18102 bt_instantiate_type_proc, &storage);
18106 /* Given a function DECL, which is a specialization of TMPL, modify
18107 DECL to be a re-instantiation of TMPL with the same template
18108 arguments. TMPL should be the template into which tsubst'ing
18109 should occur for DECL, not the most general template.
18111 One reason for doing this is a scenario like this:
18114 void f(const T&, int i);
18116 void g() { f(3, 7); }
18119 void f(const T& t, const int i) { }
18121 Note that when the template is first instantiated, with
18122 instantiate_template, the resulting DECL will have no name for the
18123 first parameter, and the wrong type for the second. So, when we go
18124 to instantiate the DECL, we regenerate it. */
18127 regenerate_decl_from_template (tree decl, tree tmpl)
18129 /* The arguments used to instantiate DECL, from the most general
18134 args = DECL_TI_ARGS (decl);
18135 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
18137 /* Make sure that we can see identifiers, and compute access
18139 push_access_scope (decl);
18141 if (TREE_CODE (decl) == FUNCTION_DECL)
18149 args_depth = TMPL_ARGS_DEPTH (args);
18150 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
18151 if (args_depth > parms_depth)
18152 args = get_innermost_template_args (args, parms_depth);
18154 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
18155 args, tf_error, NULL_TREE,
18156 /*defer_ok*/false);
18157 if (specs && specs != error_mark_node)
18158 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
18161 /* Merge parameter declarations. */
18162 decl_parm = skip_artificial_parms_for (decl,
18163 DECL_ARGUMENTS (decl));
18165 = skip_artificial_parms_for (code_pattern,
18166 DECL_ARGUMENTS (code_pattern));
18167 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
18172 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18173 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
18174 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
18176 parm_type = type_decays_to (parm_type);
18177 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18178 TREE_TYPE (decl_parm) = parm_type;
18179 attributes = DECL_ATTRIBUTES (pattern_parm);
18180 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18182 DECL_ATTRIBUTES (decl_parm) = attributes;
18183 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18185 decl_parm = DECL_CHAIN (decl_parm);
18186 pattern_parm = DECL_CHAIN (pattern_parm);
18188 /* Merge any parameters that match with the function parameter
18190 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
18193 tree expanded_types;
18194 /* Expand the TYPE_PACK_EXPANSION that provides the types for
18195 the parameters in this function parameter pack. */
18196 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
18197 args, tf_error, NULL_TREE);
18198 len = TREE_VEC_LENGTH (expanded_types);
18199 for (i = 0; i < len; i++)
18204 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18205 /* Rename the parameter to include the index. */
18206 DECL_NAME (decl_parm) =
18207 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
18208 parm_type = TREE_VEC_ELT (expanded_types, i);
18209 parm_type = type_decays_to (parm_type);
18210 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18211 TREE_TYPE (decl_parm) = parm_type;
18212 attributes = DECL_ATTRIBUTES (pattern_parm);
18213 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18215 DECL_ATTRIBUTES (decl_parm) = attributes;
18216 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18218 decl_parm = DECL_CHAIN (decl_parm);
18221 /* Merge additional specifiers from the CODE_PATTERN. */
18222 if (DECL_DECLARED_INLINE_P (code_pattern)
18223 && !DECL_DECLARED_INLINE_P (decl))
18224 DECL_DECLARED_INLINE_P (decl) = 1;
18226 else if (TREE_CODE (decl) == VAR_DECL)
18228 DECL_INITIAL (decl) =
18229 tsubst_expr (DECL_INITIAL (code_pattern), args,
18230 tf_error, DECL_TI_TEMPLATE (decl),
18231 /*integral_constant_expression_p=*/false);
18232 if (VAR_HAD_UNKNOWN_BOUND (decl))
18233 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
18234 tf_error, DECL_TI_TEMPLATE (decl));
18237 gcc_unreachable ();
18239 pop_access_scope (decl);
18242 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
18243 substituted to get DECL. */
18246 template_for_substitution (tree decl)
18248 tree tmpl = DECL_TI_TEMPLATE (decl);
18250 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
18251 for the instantiation. This is not always the most general
18252 template. Consider, for example:
18255 struct S { template <class U> void f();
18256 template <> void f<int>(); };
18258 and an instantiation of S<double>::f<int>. We want TD to be the
18259 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
18260 while (/* An instantiation cannot have a definition, so we need a
18261 more general template. */
18262 DECL_TEMPLATE_INSTANTIATION (tmpl)
18263 /* We must also deal with friend templates. Given:
18265 template <class T> struct S {
18266 template <class U> friend void f() {};
18269 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
18270 so far as the language is concerned, but that's still
18271 where we get the pattern for the instantiation from. On
18272 other hand, if the definition comes outside the class, say:
18274 template <class T> struct S {
18275 template <class U> friend void f();
18277 template <class U> friend void f() {}
18279 we don't need to look any further. That's what the check for
18280 DECL_INITIAL is for. */
18281 || (TREE_CODE (decl) == FUNCTION_DECL
18282 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
18283 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
18285 /* The present template, TD, should not be a definition. If it
18286 were a definition, we should be using it! Note that we
18287 cannot restructure the loop to just keep going until we find
18288 a template with a definition, since that might go too far if
18289 a specialization was declared, but not defined. */
18290 gcc_assert (TREE_CODE (decl) != VAR_DECL
18291 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
18293 /* Fetch the more general template. */
18294 tmpl = DECL_TI_TEMPLATE (tmpl);
18300 /* Returns true if we need to instantiate this template instance even if we
18301 know we aren't going to emit it.. */
18304 always_instantiate_p (tree decl)
18306 /* We always instantiate inline functions so that we can inline them. An
18307 explicit instantiation declaration prohibits implicit instantiation of
18308 non-inline functions. With high levels of optimization, we would
18309 normally inline non-inline functions -- but we're not allowed to do
18310 that for "extern template" functions. Therefore, we check
18311 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
18312 return ((TREE_CODE (decl) == FUNCTION_DECL
18313 && DECL_DECLARED_INLINE_P (decl))
18314 /* And we need to instantiate static data members so that
18315 their initializers are available in integral constant
18317 || (TREE_CODE (decl) == VAR_DECL
18318 && decl_maybe_constant_var_p (decl)));
18321 /* If FN has a noexcept-specifier that hasn't been instantiated yet,
18322 instantiate it now, modifying TREE_TYPE (fn). */
18325 maybe_instantiate_noexcept (tree fn)
18327 tree fntype, spec, noex, clone;
18329 if (DECL_CLONED_FUNCTION_P (fn))
18330 fn = DECL_CLONED_FUNCTION (fn);
18331 fntype = TREE_TYPE (fn);
18332 spec = TYPE_RAISES_EXCEPTIONS (fntype);
18334 if (!DEFERRED_NOEXCEPT_SPEC_P (spec))
18337 noex = TREE_PURPOSE (spec);
18339 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT)
18341 if (push_tinst_level (fn))
18343 push_access_scope (fn);
18344 input_location = DECL_SOURCE_LOCATION (fn);
18345 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
18346 DEFERRED_NOEXCEPT_ARGS (noex),
18347 tf_warning_or_error, fn,
18348 /*function_p=*/false,
18349 /*integral_constant_expression_p=*/true);
18350 pop_access_scope (fn);
18351 pop_tinst_level ();
18352 spec = build_noexcept_spec (noex, tf_warning_or_error);
18353 if (spec == error_mark_node)
18354 spec = noexcept_false_spec;
18357 spec = noexcept_false_spec;
18361 /* This is an implicitly declared function, so NOEX is a list of
18362 other functions to evaluate and merge. */
18364 spec = noexcept_true_spec;
18365 for (elt = noex; elt; elt = OVL_NEXT (elt))
18367 tree fn = OVL_CURRENT (elt);
18369 maybe_instantiate_noexcept (fn);
18370 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
18371 spec = merge_exception_specifiers (spec, subspec, NULL_TREE);
18375 TREE_TYPE (fn) = build_exception_variant (fntype, spec);
18377 FOR_EACH_CLONE (clone, fn)
18379 if (TREE_TYPE (clone) == fntype)
18380 TREE_TYPE (clone) = TREE_TYPE (fn);
18382 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec);
18386 /* Produce the definition of D, a _DECL generated from a template. If
18387 DEFER_OK is nonzero, then we don't have to actually do the
18388 instantiation now; we just have to do it sometime. Normally it is
18389 an error if this is an explicit instantiation but D is undefined.
18390 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
18391 explicitly instantiated class template. */
18394 instantiate_decl (tree d, int defer_ok,
18395 bool expl_inst_class_mem_p)
18397 tree tmpl = DECL_TI_TEMPLATE (d);
18404 bool pattern_defined;
18406 location_t saved_loc = input_location;
18409 /* This function should only be used to instantiate templates for
18410 functions and static member variables. */
18411 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
18412 || TREE_CODE (d) == VAR_DECL);
18414 /* Variables are never deferred; if instantiation is required, they
18415 are instantiated right away. That allows for better code in the
18416 case that an expression refers to the value of the variable --
18417 if the variable has a constant value the referring expression can
18418 take advantage of that fact. */
18419 if (TREE_CODE (d) == VAR_DECL
18420 || DECL_DECLARED_CONSTEXPR_P (d))
18423 /* Don't instantiate cloned functions. Instead, instantiate the
18424 functions they cloned. */
18425 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
18426 d = DECL_CLONED_FUNCTION (d);
18428 if (DECL_TEMPLATE_INSTANTIATED (d)
18429 || (TREE_CODE (d) == FUNCTION_DECL
18430 && DECL_DEFAULTED_FN (d) && DECL_INITIAL (d))
18431 || DECL_TEMPLATE_SPECIALIZATION (d))
18432 /* D has already been instantiated or explicitly specialized, so
18433 there's nothing for us to do here.
18435 It might seem reasonable to check whether or not D is an explicit
18436 instantiation, and, if so, stop here. But when an explicit
18437 instantiation is deferred until the end of the compilation,
18438 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
18439 the instantiation. */
18442 /* Check to see whether we know that this template will be
18443 instantiated in some other file, as with "extern template"
18445 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
18447 /* In general, we do not instantiate such templates. */
18448 if (external_p && !always_instantiate_p (d))
18451 gen_tmpl = most_general_template (tmpl);
18452 gen_args = DECL_TI_ARGS (d);
18454 if (tmpl != gen_tmpl)
18455 /* We should already have the extra args. */
18456 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
18457 == TMPL_ARGS_DEPTH (gen_args));
18458 /* And what's in the hash table should match D. */
18459 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
18460 || spec == NULL_TREE);
18462 /* This needs to happen before any tsubsting. */
18463 if (! push_tinst_level (d))
18466 timevar_push (TV_TEMPLATE_INST);
18468 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
18469 for the instantiation. */
18470 td = template_for_substitution (d);
18471 code_pattern = DECL_TEMPLATE_RESULT (td);
18473 /* We should never be trying to instantiate a member of a class
18474 template or partial specialization. */
18475 gcc_assert (d != code_pattern);
18477 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
18478 || DECL_TEMPLATE_SPECIALIZATION (td))
18479 /* In the case of a friend template whose definition is provided
18480 outside the class, we may have too many arguments. Drop the
18481 ones we don't need. The same is true for specializations. */
18482 args = get_innermost_template_args
18483 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
18487 if (TREE_CODE (d) == FUNCTION_DECL)
18488 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
18489 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
18491 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
18493 /* We may be in the middle of deferred access check. Disable it now. */
18494 push_deferring_access_checks (dk_no_deferred);
18496 /* Unless an explicit instantiation directive has already determined
18497 the linkage of D, remember that a definition is available for
18499 if (pattern_defined
18500 && !DECL_INTERFACE_KNOWN (d)
18501 && !DECL_NOT_REALLY_EXTERN (d))
18502 mark_definable (d);
18504 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
18505 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
18506 input_location = DECL_SOURCE_LOCATION (d);
18508 /* If D is a member of an explicitly instantiated class template,
18509 and no definition is available, treat it like an implicit
18511 if (!pattern_defined && expl_inst_class_mem_p
18512 && DECL_EXPLICIT_INSTANTIATION (d))
18514 /* Leave linkage flags alone on instantiations with anonymous
18516 if (TREE_PUBLIC (d))
18518 DECL_NOT_REALLY_EXTERN (d) = 0;
18519 DECL_INTERFACE_KNOWN (d) = 0;
18521 SET_DECL_IMPLICIT_INSTANTIATION (d);
18524 if (TREE_CODE (d) == FUNCTION_DECL)
18525 maybe_instantiate_noexcept (d);
18527 /* Recheck the substitutions to obtain any warning messages
18528 about ignoring cv qualifiers. Don't do this for artificial decls,
18529 as it breaks the context-sensitive substitution for lambda op(). */
18530 if (!defer_ok && !DECL_ARTIFICIAL (d))
18532 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
18533 tree type = TREE_TYPE (gen);
18535 /* Make sure that we can see identifiers, and compute access
18536 correctly. D is already the target FUNCTION_DECL with the
18538 push_access_scope (d);
18540 if (TREE_CODE (gen) == FUNCTION_DECL)
18542 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
18543 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
18544 d, /*defer_ok*/true);
18545 /* Don't simply tsubst the function type, as that will give
18546 duplicate warnings about poor parameter qualifications.
18547 The function arguments are the same as the decl_arguments
18548 without the top level cv qualifiers. */
18549 type = TREE_TYPE (type);
18551 tsubst (type, gen_args, tf_warning_or_error, d);
18553 pop_access_scope (d);
18556 /* Defer all other templates, unless we have been explicitly
18557 forbidden from doing so. */
18558 if (/* If there is no definition, we cannot instantiate the
18561 /* If it's OK to postpone instantiation, do so. */
18563 /* If this is a static data member that will be defined
18564 elsewhere, we don't want to instantiate the entire data
18565 member, but we do want to instantiate the initializer so that
18566 we can substitute that elsewhere. */
18567 || (external_p && TREE_CODE (d) == VAR_DECL))
18569 /* The definition of the static data member is now required so
18570 we must substitute the initializer. */
18571 if (TREE_CODE (d) == VAR_DECL
18572 && !DECL_INITIAL (d)
18573 && DECL_INITIAL (code_pattern))
18577 bool const_init = false;
18579 ns = decl_namespace_context (d);
18580 push_nested_namespace (ns);
18581 push_nested_class (DECL_CONTEXT (d));
18582 init = tsubst_expr (DECL_INITIAL (code_pattern),
18584 tf_warning_or_error, NULL_TREE,
18585 /*integral_constant_expression_p=*/false);
18586 /* Make sure the initializer is still constant, in case of
18587 circular dependency (template/instantiate6.C). */
18589 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18590 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
18591 /*asmspec_tree=*/NULL_TREE,
18592 LOOKUP_ONLYCONVERTING);
18593 pop_nested_class ();
18594 pop_nested_namespace (ns);
18597 /* We restore the source position here because it's used by
18598 add_pending_template. */
18599 input_location = saved_loc;
18601 if (at_eof && !pattern_defined
18602 && DECL_EXPLICIT_INSTANTIATION (d)
18603 && DECL_NOT_REALLY_EXTERN (d))
18606 The definition of a non-exported function template, a
18607 non-exported member function template, or a non-exported
18608 member function or static data member of a class template
18609 shall be present in every translation unit in which it is
18610 explicitly instantiated. */
18611 permerror (input_location, "explicit instantiation of %qD "
18612 "but no definition available", d);
18614 /* If we're in unevaluated context, we just wanted to get the
18615 constant value; this isn't an odr use, so don't queue
18616 a full instantiation. */
18617 if (cp_unevaluated_operand != 0)
18619 /* ??? Historically, we have instantiated inline functions, even
18620 when marked as "extern template". */
18621 if (!(external_p && TREE_CODE (d) == VAR_DECL))
18622 add_pending_template (d);
18625 /* Tell the repository that D is available in this translation unit
18626 -- and see if it is supposed to be instantiated here. */
18627 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
18629 /* In a PCH file, despite the fact that the repository hasn't
18630 requested instantiation in the PCH it is still possible that
18631 an instantiation will be required in a file that includes the
18634 add_pending_template (d);
18635 /* Instantiate inline functions so that the inliner can do its
18636 job, even though we'll not be emitting a copy of this
18638 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
18642 need_push = !cfun || !global_bindings_p ();
18644 push_to_top_level ();
18646 /* Mark D as instantiated so that recursive calls to
18647 instantiate_decl do not try to instantiate it again. */
18648 DECL_TEMPLATE_INSTANTIATED (d) = 1;
18650 /* Regenerate the declaration in case the template has been modified
18651 by a subsequent redeclaration. */
18652 regenerate_decl_from_template (d, td);
18654 /* We already set the file and line above. Reset them now in case
18655 they changed as a result of calling regenerate_decl_from_template. */
18656 input_location = DECL_SOURCE_LOCATION (d);
18658 if (TREE_CODE (d) == VAR_DECL)
18661 bool const_init = false;
18663 /* Clear out DECL_RTL; whatever was there before may not be right
18664 since we've reset the type of the declaration. */
18665 SET_DECL_RTL (d, NULL);
18666 DECL_IN_AGGR_P (d) = 0;
18668 /* The initializer is placed in DECL_INITIAL by
18669 regenerate_decl_from_template so we don't need to
18670 push/pop_access_scope again here. Pull it out so that
18671 cp_finish_decl can process it. */
18672 init = DECL_INITIAL (d);
18673 DECL_INITIAL (d) = NULL_TREE;
18674 DECL_INITIALIZED_P (d) = 0;
18676 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
18677 initializer. That function will defer actual emission until
18678 we have a chance to determine linkage. */
18679 DECL_EXTERNAL (d) = 0;
18681 /* Enter the scope of D so that access-checking works correctly. */
18682 push_nested_class (DECL_CONTEXT (d));
18683 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18684 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
18685 pop_nested_class ();
18687 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
18688 synthesize_method (d);
18689 else if (TREE_CODE (d) == FUNCTION_DECL)
18691 htab_t saved_local_specializations;
18696 /* Save away the current list, in case we are instantiating one
18697 template from within the body of another. */
18698 saved_local_specializations = local_specializations;
18700 /* Set up the list of local specializations. */
18701 local_specializations = htab_create (37,
18702 hash_local_specialization,
18703 eq_local_specializations,
18706 /* Set up context. */
18707 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
18709 /* Create substitution entries for the parameters. */
18710 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
18711 tmpl_parm = DECL_ARGUMENTS (subst_decl);
18712 spec_parm = DECL_ARGUMENTS (d);
18713 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
18715 register_local_specialization (spec_parm, tmpl_parm);
18716 spec_parm = skip_artificial_parms_for (d, spec_parm);
18717 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
18719 for (; tmpl_parm; tmpl_parm = DECL_CHAIN (tmpl_parm))
18721 if (!FUNCTION_PARAMETER_PACK_P (tmpl_parm))
18723 register_local_specialization (spec_parm, tmpl_parm);
18724 spec_parm = DECL_CHAIN (spec_parm);
18728 /* Register the (value) argument pack as a specialization of
18729 TMPL_PARM, then move on. */
18730 tree argpack = extract_fnparm_pack (tmpl_parm, &spec_parm);
18731 register_local_specialization (argpack, tmpl_parm);
18734 gcc_assert (!spec_parm);
18736 /* Substitute into the body of the function. */
18737 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
18738 tf_warning_or_error, tmpl,
18739 /*integral_constant_expression_p=*/false);
18741 /* Set the current input_location to the end of the function
18742 so that finish_function knows where we are. */
18743 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
18745 /* We don't need the local specializations any more. */
18746 htab_delete (local_specializations);
18747 local_specializations = saved_local_specializations;
18749 /* Finish the function. */
18750 d = finish_function (0);
18751 expand_or_defer_fn (d);
18754 /* We're not deferring instantiation any more. */
18755 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
18758 pop_from_top_level ();
18761 input_location = saved_loc;
18762 pop_deferring_access_checks ();
18763 pop_tinst_level ();
18765 timevar_pop (TV_TEMPLATE_INST);
18770 /* Run through the list of templates that we wish we could
18771 instantiate, and instantiate any we can. RETRIES is the
18772 number of times we retry pending template instantiation. */
18775 instantiate_pending_templates (int retries)
18778 location_t saved_loc = input_location;
18780 /* Instantiating templates may trigger vtable generation. This in turn
18781 may require further template instantiations. We place a limit here
18782 to avoid infinite loop. */
18783 if (pending_templates && retries >= max_tinst_depth)
18785 tree decl = pending_templates->tinst->decl;
18787 error ("template instantiation depth exceeds maximum of %d"
18788 " instantiating %q+D, possibly from virtual table generation"
18789 " (use -ftemplate-depth= to increase the maximum)",
18790 max_tinst_depth, decl);
18791 if (TREE_CODE (decl) == FUNCTION_DECL)
18792 /* Pretend that we defined it. */
18793 DECL_INITIAL (decl) = error_mark_node;
18799 struct pending_template **t = &pending_templates;
18800 struct pending_template *last = NULL;
18804 tree instantiation = reopen_tinst_level ((*t)->tinst);
18805 bool complete = false;
18807 if (TYPE_P (instantiation))
18811 if (!COMPLETE_TYPE_P (instantiation))
18813 instantiate_class_template (instantiation);
18814 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
18815 for (fn = TYPE_METHODS (instantiation);
18817 fn = TREE_CHAIN (fn))
18818 if (! DECL_ARTIFICIAL (fn))
18819 instantiate_decl (fn,
18821 /*expl_inst_class_mem_p=*/false);
18822 if (COMPLETE_TYPE_P (instantiation))
18826 complete = COMPLETE_TYPE_P (instantiation);
18830 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
18831 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
18834 = instantiate_decl (instantiation,
18836 /*expl_inst_class_mem_p=*/false);
18837 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
18841 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
18842 || DECL_TEMPLATE_INSTANTIATED (instantiation));
18846 /* If INSTANTIATION has been instantiated, then we don't
18847 need to consider it again in the future. */
18855 current_tinst_level = NULL;
18857 last_pending_template = last;
18859 while (reconsider);
18861 input_location = saved_loc;
18864 /* Substitute ARGVEC into T, which is a list of initializers for
18865 either base class or a non-static data member. The TREE_PURPOSEs
18866 are DECLs, and the TREE_VALUEs are the initializer values. Used by
18867 instantiate_decl. */
18870 tsubst_initializer_list (tree t, tree argvec)
18872 tree inits = NULL_TREE;
18874 for (; t; t = TREE_CHAIN (t))
18878 tree expanded_bases = NULL_TREE;
18879 tree expanded_arguments = NULL_TREE;
18882 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
18887 /* Expand the base class expansion type into separate base
18889 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
18890 tf_warning_or_error,
18892 if (expanded_bases == error_mark_node)
18895 /* We'll be building separate TREE_LISTs of arguments for
18897 len = TREE_VEC_LENGTH (expanded_bases);
18898 expanded_arguments = make_tree_vec (len);
18899 for (i = 0; i < len; i++)
18900 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
18902 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
18903 expand each argument in the TREE_VALUE of t. */
18904 expr = make_node (EXPR_PACK_EXPANSION);
18905 PACK_EXPANSION_PARAMETER_PACKS (expr) =
18906 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
18908 if (TREE_VALUE (t) == void_type_node)
18909 /* VOID_TYPE_NODE is used to indicate
18910 value-initialization. */
18912 for (i = 0; i < len; i++)
18913 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
18917 /* Substitute parameter packs into each argument in the
18919 in_base_initializer = 1;
18920 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
18922 tree expanded_exprs;
18924 /* Expand the argument. */
18925 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
18927 = tsubst_pack_expansion (expr, argvec,
18928 tf_warning_or_error,
18930 if (expanded_exprs == error_mark_node)
18933 /* Prepend each of the expanded expressions to the
18934 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
18935 for (i = 0; i < len; i++)
18937 TREE_VEC_ELT (expanded_arguments, i) =
18938 tree_cons (NULL_TREE,
18939 TREE_VEC_ELT (expanded_exprs, i),
18940 TREE_VEC_ELT (expanded_arguments, i));
18943 in_base_initializer = 0;
18945 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
18946 since we built them backwards. */
18947 for (i = 0; i < len; i++)
18949 TREE_VEC_ELT (expanded_arguments, i) =
18950 nreverse (TREE_VEC_ELT (expanded_arguments, i));
18955 for (i = 0; i < len; ++i)
18957 if (expanded_bases)
18959 decl = TREE_VEC_ELT (expanded_bases, i);
18960 decl = expand_member_init (decl);
18961 init = TREE_VEC_ELT (expanded_arguments, i);
18965 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
18966 tf_warning_or_error, NULL_TREE);
18968 decl = expand_member_init (decl);
18969 if (decl && !DECL_P (decl))
18970 in_base_initializer = 1;
18972 init = TREE_VALUE (t);
18973 if (init != void_type_node)
18974 init = tsubst_expr (init, argvec,
18975 tf_warning_or_error, NULL_TREE,
18976 /*integral_constant_expression_p=*/false);
18977 in_base_initializer = 0;
18982 init = build_tree_list (decl, init);
18983 TREE_CHAIN (init) = inits;
18991 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
18994 set_current_access_from_decl (tree decl)
18996 if (TREE_PRIVATE (decl))
18997 current_access_specifier = access_private_node;
18998 else if (TREE_PROTECTED (decl))
18999 current_access_specifier = access_protected_node;
19001 current_access_specifier = access_public_node;
19004 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
19005 is the instantiation (which should have been created with
19006 start_enum) and ARGS are the template arguments to use. */
19009 tsubst_enum (tree tag, tree newtag, tree args)
19013 if (SCOPED_ENUM_P (newtag))
19014 begin_scope (sk_scoped_enum, newtag);
19016 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
19021 decl = TREE_VALUE (e);
19022 /* Note that in a template enum, the TREE_VALUE is the
19023 CONST_DECL, not the corresponding INTEGER_CST. */
19024 value = tsubst_expr (DECL_INITIAL (decl),
19025 args, tf_warning_or_error, NULL_TREE,
19026 /*integral_constant_expression_p=*/true);
19028 /* Give this enumeration constant the correct access. */
19029 set_current_access_from_decl (decl);
19031 /* Actually build the enumerator itself. */
19033 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
19036 if (SCOPED_ENUM_P (newtag))
19039 finish_enum_value_list (newtag);
19040 finish_enum (newtag);
19042 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
19043 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
19046 /* DECL is a FUNCTION_DECL that is a template specialization. Return
19047 its type -- but without substituting the innermost set of template
19048 arguments. So, innermost set of template parameters will appear in
19052 get_mostly_instantiated_function_type (tree decl)
19060 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
19061 targs = DECL_TI_ARGS (decl);
19062 tparms = DECL_TEMPLATE_PARMS (tmpl);
19063 parm_depth = TMPL_PARMS_DEPTH (tparms);
19065 /* There should be as many levels of arguments as there are levels
19067 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
19069 fn_type = TREE_TYPE (tmpl);
19071 if (parm_depth == 1)
19072 /* No substitution is necessary. */
19079 /* Replace the innermost level of the TARGS with NULL_TREEs to
19080 let tsubst know not to substitute for those parameters. */
19081 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
19082 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
19083 SET_TMPL_ARGS_LEVEL (partial_args, i,
19084 TMPL_ARGS_LEVEL (targs, i));
19085 SET_TMPL_ARGS_LEVEL (partial_args,
19086 TMPL_ARGS_DEPTH (targs),
19087 make_tree_vec (DECL_NTPARMS (tmpl)));
19089 /* Make sure that we can see identifiers, and compute access
19091 push_access_scope (decl);
19093 ++processing_template_decl;
19094 /* Now, do the (partial) substitution to figure out the
19095 appropriate function type. */
19096 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
19097 --processing_template_decl;
19099 /* Substitute into the template parameters to obtain the real
19100 innermost set of parameters. This step is important if the
19101 innermost set of template parameters contains value
19102 parameters whose types depend on outer template parameters. */
19103 TREE_VEC_LENGTH (partial_args)--;
19104 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
19106 pop_access_scope (decl);
19112 /* Return truthvalue if we're processing a template different from
19113 the last one involved in diagnostics. */
19115 problematic_instantiation_changed (void)
19117 return current_tinst_level != last_error_tinst_level;
19120 /* Remember current template involved in diagnostics. */
19122 record_last_problematic_instantiation (void)
19124 last_error_tinst_level = current_tinst_level;
19127 struct tinst_level *
19128 current_instantiation (void)
19130 return current_tinst_level;
19133 /* [temp.param] Check that template non-type parm TYPE is of an allowable
19134 type. Return zero for ok, nonzero for disallowed. Issue error and
19135 warning messages under control of COMPLAIN. */
19138 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
19140 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
19142 else if (POINTER_TYPE_P (type))
19144 else if (TYPE_PTR_TO_MEMBER_P (type))
19146 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
19148 else if (TREE_CODE (type) == TYPENAME_TYPE)
19150 else if (TREE_CODE (type) == DECLTYPE_TYPE)
19152 else if (TREE_CODE (type) == NULLPTR_TYPE)
19155 if (complain & tf_error)
19157 if (type == error_mark_node)
19158 inform (input_location, "invalid template non-type parameter");
19160 error ("%q#T is not a valid type for a template non-type parameter",
19166 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
19167 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
19170 dependent_type_p_r (tree type)
19176 A type is dependent if it is:
19178 -- a template parameter. Template template parameters are types
19179 for us (since TYPE_P holds true for them) so we handle
19181 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19182 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
19184 /* -- a qualified-id with a nested-name-specifier which contains a
19185 class-name that names a dependent type or whose unqualified-id
19186 names a dependent type. */
19187 if (TREE_CODE (type) == TYPENAME_TYPE)
19189 /* -- a cv-qualified type where the cv-unqualified type is
19191 type = TYPE_MAIN_VARIANT (type);
19192 /* -- a compound type constructed from any dependent type. */
19193 if (TYPE_PTR_TO_MEMBER_P (type))
19194 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
19195 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
19197 else if (TREE_CODE (type) == POINTER_TYPE
19198 || TREE_CODE (type) == REFERENCE_TYPE)
19199 return dependent_type_p (TREE_TYPE (type));
19200 else if (TREE_CODE (type) == FUNCTION_TYPE
19201 || TREE_CODE (type) == METHOD_TYPE)
19205 if (dependent_type_p (TREE_TYPE (type)))
19207 for (arg_type = TYPE_ARG_TYPES (type);
19209 arg_type = TREE_CHAIN (arg_type))
19210 if (dependent_type_p (TREE_VALUE (arg_type)))
19214 /* -- an array type constructed from any dependent type or whose
19215 size is specified by a constant expression that is
19218 We checked for type- and value-dependence of the bounds in
19219 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
19220 if (TREE_CODE (type) == ARRAY_TYPE)
19222 if (TYPE_DOMAIN (type)
19223 && dependent_type_p (TYPE_DOMAIN (type)))
19225 return dependent_type_p (TREE_TYPE (type));
19228 /* -- a template-id in which either the template name is a template
19230 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
19232 /* ... or any of the template arguments is a dependent type or
19233 an expression that is type-dependent or value-dependent. */
19234 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
19235 && (any_dependent_template_arguments_p
19236 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
19239 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
19240 dependent; if the argument of the `typeof' expression is not
19241 type-dependent, then it should already been have resolved. */
19242 if (TREE_CODE (type) == TYPEOF_TYPE
19243 || TREE_CODE (type) == DECLTYPE_TYPE
19244 || TREE_CODE (type) == UNDERLYING_TYPE)
19247 /* A template argument pack is dependent if any of its packed
19249 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
19251 tree args = ARGUMENT_PACK_ARGS (type);
19252 int i, len = TREE_VEC_LENGTH (args);
19253 for (i = 0; i < len; ++i)
19254 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19258 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
19259 be template parameters. */
19260 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
19263 /* The standard does not specifically mention types that are local
19264 to template functions or local classes, but they should be
19265 considered dependent too. For example:
19267 template <int I> void f() {
19272 The size of `E' cannot be known until the value of `I' has been
19273 determined. Therefore, `E' must be considered dependent. */
19274 scope = TYPE_CONTEXT (type);
19275 if (scope && TYPE_P (scope))
19276 return dependent_type_p (scope);
19277 /* Don't use type_dependent_expression_p here, as it can lead
19278 to infinite recursion trying to determine whether a lambda
19279 nested in a lambda is dependent (c++/47687). */
19280 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
19281 && DECL_LANG_SPECIFIC (scope)
19282 && DECL_TEMPLATE_INFO (scope)
19283 && (any_dependent_template_arguments_p
19284 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
19287 /* Other types are non-dependent. */
19291 /* Returns TRUE if TYPE is dependent, in the sense of
19292 [temp.dep.type]. Note that a NULL type is considered dependent. */
19295 dependent_type_p (tree type)
19297 /* If there are no template parameters in scope, then there can't be
19298 any dependent types. */
19299 if (!processing_template_decl)
19301 /* If we are not processing a template, then nobody should be
19302 providing us with a dependent type. */
19304 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
19308 /* If the type is NULL, we have not computed a type for the entity
19309 in question; in that case, the type is dependent. */
19313 /* Erroneous types can be considered non-dependent. */
19314 if (type == error_mark_node)
19317 /* If we have not already computed the appropriate value for TYPE,
19319 if (!TYPE_DEPENDENT_P_VALID (type))
19321 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
19322 TYPE_DEPENDENT_P_VALID (type) = 1;
19325 return TYPE_DEPENDENT_P (type);
19328 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
19329 lookup. In other words, a dependent type that is not the current
19333 dependent_scope_p (tree scope)
19335 return (scope && TYPE_P (scope) && dependent_type_p (scope)
19336 && !currently_open_class (scope));
19339 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
19340 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
19343 /* Note that this predicate is not appropriate for general expressions;
19344 only constant expressions (that satisfy potential_constant_expression)
19345 can be tested for value dependence.
19347 We should really also have a predicate for "instantiation-dependent".
19349 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
19350 (what about instantiation-dependent constant-expressions?)
19351 is_late_template_attribute: defer if instantiation-dependent.
19352 compute_array_index_type: proceed if constant and not t- or v-dependent
19353 if instantiation-dependent, need to remember full expression
19354 uses_template_parms: FIXME - need to audit callers
19355 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
19356 dependent_type_p [array_type]: dependent if index type is dependent
19358 static_assert - instantiation-dependent */
19361 value_dependent_expression_p (tree expression)
19363 if (!processing_template_decl)
19366 /* A name declared with a dependent type. */
19367 if (DECL_P (expression) && type_dependent_expression_p (expression))
19370 switch (TREE_CODE (expression))
19372 case IDENTIFIER_NODE:
19373 /* A name that has not been looked up -- must be dependent. */
19376 case TEMPLATE_PARM_INDEX:
19377 /* A non-type template parm. */
19381 /* A non-type template parm. */
19382 if (DECL_TEMPLATE_PARM_P (expression))
19384 return value_dependent_expression_p (DECL_INITIAL (expression));
19387 /* A constant with literal type and is initialized
19388 with an expression that is value-dependent. */
19389 if (DECL_INITIAL (expression)
19390 && decl_constant_var_p (expression)
19391 && value_dependent_expression_p (DECL_INITIAL (expression)))
19395 case DYNAMIC_CAST_EXPR:
19396 case STATIC_CAST_EXPR:
19397 case CONST_CAST_EXPR:
19398 case REINTERPRET_CAST_EXPR:
19400 /* These expressions are value-dependent if the type to which
19401 the cast occurs is dependent or the expression being casted
19402 is value-dependent. */
19404 tree type = TREE_TYPE (expression);
19406 if (dependent_type_p (type))
19409 /* A functional cast has a list of operands. */
19410 expression = TREE_OPERAND (expression, 0);
19413 /* If there are no operands, it must be an expression such
19414 as "int()". This should not happen for aggregate types
19415 because it would form non-constant expressions. */
19416 gcc_assert (cxx_dialect >= cxx0x
19417 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
19422 if (TREE_CODE (expression) == TREE_LIST)
19423 return any_value_dependent_elements_p (expression);
19425 return value_dependent_expression_p (expression);
19431 /* A `sizeof' expression is value-dependent if the operand is
19432 type-dependent or is a pack expansion. */
19433 expression = TREE_OPERAND (expression, 0);
19434 if (PACK_EXPANSION_P (expression))
19436 else if (TYPE_P (expression))
19437 return dependent_type_p (expression);
19438 return type_dependent_expression_p (expression);
19440 case AT_ENCODE_EXPR:
19441 /* An 'encode' expression is value-dependent if the operand is
19443 expression = TREE_OPERAND (expression, 0);
19444 return dependent_type_p (expression);
19446 case NOEXCEPT_EXPR:
19447 expression = TREE_OPERAND (expression, 0);
19448 return type_dependent_expression_p (expression);
19452 tree name = TREE_OPERAND (expression, 1);
19453 return value_dependent_expression_p (name);
19456 case COMPONENT_REF:
19457 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
19458 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
19460 case NONTYPE_ARGUMENT_PACK:
19461 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
19462 is value-dependent. */
19464 tree values = ARGUMENT_PACK_ARGS (expression);
19465 int i, len = TREE_VEC_LENGTH (values);
19467 for (i = 0; i < len; ++i)
19468 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
19476 tree type2 = TRAIT_EXPR_TYPE2 (expression);
19477 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
19478 || (type2 ? dependent_type_p (type2) : false));
19482 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19483 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
19486 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19487 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
19491 tree op = TREE_OPERAND (expression, 0);
19492 return (value_dependent_expression_p (op)
19493 || has_value_dependent_address (op));
19498 tree fn = get_callee_fndecl (expression);
19500 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
19502 nargs = call_expr_nargs (expression);
19503 for (i = 0; i < nargs; ++i)
19505 tree op = CALL_EXPR_ARG (expression, i);
19506 /* In a call to a constexpr member function, look through the
19507 implicit ADDR_EXPR on the object argument so that it doesn't
19508 cause the call to be considered value-dependent. We also
19509 look through it in potential_constant_expression. */
19510 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
19511 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
19512 && TREE_CODE (op) == ADDR_EXPR)
19513 op = TREE_OPERAND (op, 0);
19514 if (value_dependent_expression_p (op))
19520 case TEMPLATE_ID_EXPR:
19521 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
19523 return type_dependent_expression_p (expression);
19529 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
19530 if (value_dependent_expression_p (val))
19536 /* Treat a GNU statement expression as dependent to avoid crashing
19537 under fold_non_dependent_expr; it can't be constant. */
19541 /* A constant expression is value-dependent if any subexpression is
19542 value-dependent. */
19543 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
19545 case tcc_reference:
19547 case tcc_comparison:
19549 case tcc_expression:
19552 int i, len = cp_tree_operand_length (expression);
19554 for (i = 0; i < len; i++)
19556 tree t = TREE_OPERAND (expression, i);
19558 /* In some cases, some of the operands may be missing.l
19559 (For example, in the case of PREDECREMENT_EXPR, the
19560 amount to increment by may be missing.) That doesn't
19561 make the expression dependent. */
19562 if (t && value_dependent_expression_p (t))
19573 /* The expression is not value-dependent. */
19577 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
19578 [temp.dep.expr]. Note that an expression with no type is
19579 considered dependent. Other parts of the compiler arrange for an
19580 expression with type-dependent subexpressions to have no type, so
19581 this function doesn't have to be fully recursive. */
19584 type_dependent_expression_p (tree expression)
19586 if (!processing_template_decl)
19589 if (expression == error_mark_node)
19592 /* An unresolved name is always dependent. */
19593 if (TREE_CODE (expression) == IDENTIFIER_NODE
19594 || TREE_CODE (expression) == USING_DECL)
19597 /* Some expression forms are never type-dependent. */
19598 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
19599 || TREE_CODE (expression) == SIZEOF_EXPR
19600 || TREE_CODE (expression) == ALIGNOF_EXPR
19601 || TREE_CODE (expression) == AT_ENCODE_EXPR
19602 || TREE_CODE (expression) == NOEXCEPT_EXPR
19603 || TREE_CODE (expression) == TRAIT_EXPR
19604 || TREE_CODE (expression) == TYPEID_EXPR
19605 || TREE_CODE (expression) == DELETE_EXPR
19606 || TREE_CODE (expression) == VEC_DELETE_EXPR
19607 || TREE_CODE (expression) == THROW_EXPR)
19610 /* The types of these expressions depends only on the type to which
19611 the cast occurs. */
19612 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
19613 || TREE_CODE (expression) == STATIC_CAST_EXPR
19614 || TREE_CODE (expression) == CONST_CAST_EXPR
19615 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
19616 || TREE_CODE (expression) == IMPLICIT_CONV_EXPR
19617 || TREE_CODE (expression) == CAST_EXPR)
19618 return dependent_type_p (TREE_TYPE (expression));
19620 /* The types of these expressions depends only on the type created
19621 by the expression. */
19622 if (TREE_CODE (expression) == NEW_EXPR
19623 || TREE_CODE (expression) == VEC_NEW_EXPR)
19625 /* For NEW_EXPR tree nodes created inside a template, either
19626 the object type itself or a TREE_LIST may appear as the
19628 tree type = TREE_OPERAND (expression, 1);
19629 if (TREE_CODE (type) == TREE_LIST)
19630 /* This is an array type. We need to check array dimensions
19632 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
19633 || value_dependent_expression_p
19634 (TREE_OPERAND (TREE_VALUE (type), 1));
19636 return dependent_type_p (type);
19639 if (TREE_CODE (expression) == SCOPE_REF)
19641 tree scope = TREE_OPERAND (expression, 0);
19642 tree name = TREE_OPERAND (expression, 1);
19644 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
19645 contains an identifier associated by name lookup with one or more
19646 declarations declared with a dependent type, or...a
19647 nested-name-specifier or qualified-id that names a member of an
19648 unknown specialization. */
19649 return (type_dependent_expression_p (name)
19650 || dependent_scope_p (scope));
19653 if (TREE_CODE (expression) == FUNCTION_DECL
19654 && DECL_LANG_SPECIFIC (expression)
19655 && DECL_TEMPLATE_INFO (expression)
19656 && (any_dependent_template_arguments_p
19657 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
19660 if (TREE_CODE (expression) == TEMPLATE_DECL
19661 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
19664 if (TREE_CODE (expression) == STMT_EXPR)
19665 expression = stmt_expr_value_expr (expression);
19667 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
19672 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
19674 if (type_dependent_expression_p (elt))
19680 /* A static data member of the current instantiation with incomplete
19681 array type is type-dependent, as the definition and specializations
19682 can have different bounds. */
19683 if (TREE_CODE (expression) == VAR_DECL
19684 && DECL_CLASS_SCOPE_P (expression)
19685 && dependent_type_p (DECL_CONTEXT (expression))
19686 && VAR_HAD_UNKNOWN_BOUND (expression))
19689 if (TREE_TYPE (expression) == unknown_type_node)
19691 if (TREE_CODE (expression) == ADDR_EXPR)
19692 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
19693 if (TREE_CODE (expression) == COMPONENT_REF
19694 || TREE_CODE (expression) == OFFSET_REF)
19696 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
19698 expression = TREE_OPERAND (expression, 1);
19699 if (TREE_CODE (expression) == IDENTIFIER_NODE)
19702 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
19703 if (TREE_CODE (expression) == SCOPE_REF)
19706 if (BASELINK_P (expression))
19707 expression = BASELINK_FUNCTIONS (expression);
19709 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
19711 if (any_dependent_template_arguments_p
19712 (TREE_OPERAND (expression, 1)))
19714 expression = TREE_OPERAND (expression, 0);
19716 gcc_assert (TREE_CODE (expression) == OVERLOAD
19717 || TREE_CODE (expression) == FUNCTION_DECL);
19721 if (type_dependent_expression_p (OVL_CURRENT (expression)))
19723 expression = OVL_NEXT (expression);
19728 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
19730 return (dependent_type_p (TREE_TYPE (expression)));
19733 /* Like type_dependent_expression_p, but it also works while not processing
19734 a template definition, i.e. during substitution or mangling. */
19737 type_dependent_expression_p_push (tree expr)
19740 ++processing_template_decl;
19741 b = type_dependent_expression_p (expr);
19742 --processing_template_decl;
19746 /* Returns TRUE if ARGS contains a type-dependent expression. */
19749 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
19754 FOR_EACH_VEC_ELT (tree, args, i, arg)
19756 if (type_dependent_expression_p (arg))
19762 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19763 expressions) contains any type-dependent expressions. */
19766 any_type_dependent_elements_p (const_tree list)
19768 for (; list; list = TREE_CHAIN (list))
19769 if (value_dependent_expression_p (TREE_VALUE (list)))
19775 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19776 expressions) contains any value-dependent expressions. */
19779 any_value_dependent_elements_p (const_tree list)
19781 for (; list; list = TREE_CHAIN (list))
19782 if (value_dependent_expression_p (TREE_VALUE (list)))
19788 /* Returns TRUE if the ARG (a template argument) is dependent. */
19791 dependent_template_arg_p (tree arg)
19793 if (!processing_template_decl)
19796 /* Assume a template argument that was wrongly written by the user
19797 is dependent. This is consistent with what
19798 any_dependent_template_arguments_p [that calls this function]
19800 if (!arg || arg == error_mark_node)
19803 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
19804 arg = ARGUMENT_PACK_SELECT_ARG (arg);
19806 if (TREE_CODE (arg) == TEMPLATE_DECL
19807 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19808 return dependent_template_p (arg);
19809 else if (ARGUMENT_PACK_P (arg))
19811 tree args = ARGUMENT_PACK_ARGS (arg);
19812 int i, len = TREE_VEC_LENGTH (args);
19813 for (i = 0; i < len; ++i)
19815 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19821 else if (TYPE_P (arg))
19822 return dependent_type_p (arg);
19824 return (type_dependent_expression_p (arg)
19825 || value_dependent_expression_p (arg));
19828 /* Returns true if ARGS (a collection of template arguments) contains
19829 any types that require structural equality testing. */
19832 any_template_arguments_need_structural_equality_p (tree args)
19839 if (args == error_mark_node)
19842 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19844 tree level = TMPL_ARGS_LEVEL (args, i + 1);
19845 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19847 tree arg = TREE_VEC_ELT (level, j);
19848 tree packed_args = NULL_TREE;
19851 if (ARGUMENT_PACK_P (arg))
19853 /* Look inside the argument pack. */
19854 packed_args = ARGUMENT_PACK_ARGS (arg);
19855 len = TREE_VEC_LENGTH (packed_args);
19858 for (k = 0; k < len; ++k)
19861 arg = TREE_VEC_ELT (packed_args, k);
19863 if (error_operand_p (arg))
19865 else if (TREE_CODE (arg) == TEMPLATE_DECL
19866 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19868 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
19870 else if (!TYPE_P (arg) && TREE_TYPE (arg)
19871 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
19880 /* Returns true if ARGS (a collection of template arguments) contains
19881 any dependent arguments. */
19884 any_dependent_template_arguments_p (const_tree args)
19891 if (args == error_mark_node)
19894 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19896 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
19897 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19898 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
19905 /* Returns TRUE if the template TMPL is dependent. */
19908 dependent_template_p (tree tmpl)
19910 if (TREE_CODE (tmpl) == OVERLOAD)
19914 if (dependent_template_p (OVL_CURRENT (tmpl)))
19916 tmpl = OVL_NEXT (tmpl);
19921 /* Template template parameters are dependent. */
19922 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
19923 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
19925 /* So are names that have not been looked up. */
19926 if (TREE_CODE (tmpl) == SCOPE_REF
19927 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
19929 /* So are member templates of dependent classes. */
19930 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
19931 return dependent_type_p (DECL_CONTEXT (tmpl));
19935 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
19938 dependent_template_id_p (tree tmpl, tree args)
19940 return (dependent_template_p (tmpl)
19941 || any_dependent_template_arguments_p (args));
19944 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
19948 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
19952 if (!processing_template_decl)
19955 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
19957 tree decl = TREE_VEC_ELT (declv, i);
19958 tree init = TREE_VEC_ELT (initv, i);
19959 tree cond = TREE_VEC_ELT (condv, i);
19960 tree incr = TREE_VEC_ELT (incrv, i);
19962 if (type_dependent_expression_p (decl))
19965 if (init && type_dependent_expression_p (init))
19968 if (type_dependent_expression_p (cond))
19971 if (COMPARISON_CLASS_P (cond)
19972 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
19973 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
19976 if (TREE_CODE (incr) == MODOP_EXPR)
19978 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
19979 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
19982 else if (type_dependent_expression_p (incr))
19984 else if (TREE_CODE (incr) == MODIFY_EXPR)
19986 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
19988 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
19990 tree t = TREE_OPERAND (incr, 1);
19991 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
19992 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
20001 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
20002 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
20003 no such TYPE can be found. Note that this function peers inside
20004 uninstantiated templates and therefore should be used only in
20005 extremely limited situations. ONLY_CURRENT_P restricts this
20006 peering to the currently open classes hierarchy (which is required
20007 when comparing types). */
20010 resolve_typename_type (tree type, bool only_current_p)
20019 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
20021 scope = TYPE_CONTEXT (type);
20022 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
20023 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
20024 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
20025 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
20026 identifier of the TYPENAME_TYPE anymore.
20027 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
20028 TYPENAME_TYPE instead, we avoid messing up with a possible
20029 typedef variant case. */
20030 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
20032 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
20033 it first before we can figure out what NAME refers to. */
20034 if (TREE_CODE (scope) == TYPENAME_TYPE)
20035 scope = resolve_typename_type (scope, only_current_p);
20036 /* If we don't know what SCOPE refers to, then we cannot resolve the
20038 if (TREE_CODE (scope) == TYPENAME_TYPE)
20040 /* If the SCOPE is a template type parameter, we have no way of
20041 resolving the name. */
20042 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
20044 /* If the SCOPE is not the current instantiation, there's no reason
20045 to look inside it. */
20046 if (only_current_p && !currently_open_class (scope))
20048 /* If this is a typedef, we don't want to look inside (c++/11987). */
20049 if (typedef_variant_p (type))
20051 /* If SCOPE isn't the template itself, it will not have a valid
20052 TYPE_FIELDS list. */
20053 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
20054 /* scope is either the template itself or a compatible instantiation
20055 like X<T>, so look up the name in the original template. */
20056 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
20058 /* scope is a partial instantiation, so we can't do the lookup or we
20059 will lose the template arguments. */
20061 /* Enter the SCOPE so that name lookup will be resolved as if we
20062 were in the class definition. In particular, SCOPE will no
20063 longer be considered a dependent type. */
20064 pushed_scope = push_scope (scope);
20065 /* Look up the declaration. */
20066 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true,
20067 tf_warning_or_error);
20069 result = NULL_TREE;
20071 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
20072 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
20075 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
20076 && TREE_CODE (decl) == TYPE_DECL)
20078 result = TREE_TYPE (decl);
20079 if (result == error_mark_node)
20080 result = NULL_TREE;
20082 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
20083 && DECL_CLASS_TEMPLATE_P (decl))
20087 /* Obtain the template and the arguments. */
20088 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
20089 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
20090 /* Instantiate the template. */
20091 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
20092 /*entering_scope=*/0,
20093 tf_error | tf_user);
20094 if (result == error_mark_node)
20095 result = NULL_TREE;
20098 /* Leave the SCOPE. */
20100 pop_scope (pushed_scope);
20102 /* If we failed to resolve it, return the original typename. */
20106 /* If lookup found a typename type, resolve that too. */
20107 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
20109 /* Ill-formed programs can cause infinite recursion here, so we
20110 must catch that. */
20111 TYPENAME_IS_RESOLVING_P (type) = 1;
20112 result = resolve_typename_type (result, only_current_p);
20113 TYPENAME_IS_RESOLVING_P (type) = 0;
20116 /* Qualify the resulting type. */
20117 quals = cp_type_quals (type);
20119 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
20124 /* EXPR is an expression which is not type-dependent. Return a proxy
20125 for EXPR that can be used to compute the types of larger
20126 expressions containing EXPR. */
20129 build_non_dependent_expr (tree expr)
20133 #ifdef ENABLE_CHECKING
20134 /* Try to get a constant value for all non-type-dependent expressions in
20135 order to expose bugs in *_dependent_expression_p and constexpr. */
20136 if (cxx_dialect >= cxx0x)
20137 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none));
20140 /* Preserve OVERLOADs; the functions must be available to resolve
20143 if (TREE_CODE (inner_expr) == STMT_EXPR)
20144 inner_expr = stmt_expr_value_expr (inner_expr);
20145 if (TREE_CODE (inner_expr) == ADDR_EXPR)
20146 inner_expr = TREE_OPERAND (inner_expr, 0);
20147 if (TREE_CODE (inner_expr) == COMPONENT_REF)
20148 inner_expr = TREE_OPERAND (inner_expr, 1);
20149 if (is_overloaded_fn (inner_expr)
20150 || TREE_CODE (inner_expr) == OFFSET_REF)
20152 /* There is no need to return a proxy for a variable. */
20153 if (TREE_CODE (expr) == VAR_DECL)
20155 /* Preserve string constants; conversions from string constants to
20156 "char *" are allowed, even though normally a "const char *"
20157 cannot be used to initialize a "char *". */
20158 if (TREE_CODE (expr) == STRING_CST)
20160 /* Preserve arithmetic constants, as an optimization -- there is no
20161 reason to create a new node. */
20162 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
20164 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
20165 There is at least one place where we want to know that a
20166 particular expression is a throw-expression: when checking a ?:
20167 expression, there are special rules if the second or third
20168 argument is a throw-expression. */
20169 if (TREE_CODE (expr) == THROW_EXPR)
20172 /* Don't wrap an initializer list, we need to be able to look inside. */
20173 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
20176 if (TREE_CODE (expr) == COND_EXPR)
20177 return build3 (COND_EXPR,
20179 TREE_OPERAND (expr, 0),
20180 (TREE_OPERAND (expr, 1)
20181 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
20182 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
20183 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
20184 if (TREE_CODE (expr) == COMPOUND_EXPR
20185 && !COMPOUND_EXPR_OVERLOADED (expr))
20186 return build2 (COMPOUND_EXPR,
20188 TREE_OPERAND (expr, 0),
20189 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
20191 /* If the type is unknown, it can't really be non-dependent */
20192 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
20194 /* Otherwise, build a NON_DEPENDENT_EXPR. */
20195 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
20198 /* ARGS is a vector of expressions as arguments to a function call.
20199 Replace the arguments with equivalent non-dependent expressions.
20200 This modifies ARGS in place. */
20203 make_args_non_dependent (VEC(tree,gc) *args)
20208 FOR_EACH_VEC_ELT (tree, args, ix, arg)
20210 tree newarg = build_non_dependent_expr (arg);
20212 VEC_replace (tree, args, ix, newarg);
20216 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
20217 with a level one deeper than the actual template parms. */
20222 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
20223 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
20224 TYPE_DECL, get_identifier ("auto"), au);
20225 TYPE_STUB_DECL (au) = TYPE_NAME (au);
20226 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
20227 (0, processing_template_decl + 1, processing_template_decl + 1,
20228 0, TYPE_NAME (au), NULL_TREE);
20229 TYPE_CANONICAL (au) = canonical_type_parameter (au);
20230 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
20231 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
20236 /* Given type ARG, return std::initializer_list<ARG>. */
20241 tree std_init_list = namespace_binding
20242 (get_identifier ("initializer_list"), std_node);
20244 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
20246 error ("deducing from brace-enclosed initializer list requires "
20247 "#include <initializer_list>");
20248 return error_mark_node;
20250 argvec = make_tree_vec (1);
20251 TREE_VEC_ELT (argvec, 0) = arg;
20252 return lookup_template_class (std_init_list, argvec, NULL_TREE,
20253 NULL_TREE, 0, tf_warning_or_error);
20256 /* Replace auto in TYPE with std::initializer_list<auto>. */
20259 listify_autos (tree type, tree auto_node)
20261 tree init_auto = listify (auto_node);
20262 tree argvec = make_tree_vec (1);
20263 TREE_VEC_ELT (argvec, 0) = init_auto;
20264 if (processing_template_decl)
20265 argvec = add_to_template_args (current_template_args (), argvec);
20266 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20269 /* walk_tree helper for do_auto_deduction. */
20272 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
20275 /* Is this a variable with the type we're looking for? */
20277 && TREE_TYPE (*tp) == type)
20283 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
20284 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
20287 do_auto_deduction (tree type, tree init, tree auto_node)
20289 tree parms, tparms, targs;
20294 if (processing_template_decl
20295 && (TREE_TYPE (init) == NULL_TREE
20296 || BRACE_ENCLOSED_INITIALIZER_P (init)))
20297 /* Not enough information to try this yet. */
20300 /* The name of the object being declared shall not appear in the
20301 initializer expression. */
20302 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
20305 error ("variable %q#D with %<auto%> type used in its own "
20306 "initializer", decl);
20307 return error_mark_node;
20310 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
20311 with either a new invented type template parameter U or, if the
20312 initializer is a braced-init-list (8.5.4), with
20313 std::initializer_list<U>. */
20314 if (BRACE_ENCLOSED_INITIALIZER_P (init))
20315 type = listify_autos (type, auto_node);
20317 init = resolve_nondeduced_context (init);
20319 parms = build_tree_list (NULL_TREE, type);
20321 tparms = make_tree_vec (1);
20322 targs = make_tree_vec (1);
20323 TREE_VEC_ELT (tparms, 0)
20324 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
20325 val = type_unification_real (tparms, targs, parms, args, 1, 0,
20326 DEDUCE_CALL, LOOKUP_NORMAL,
20327 /*explain_p=*/false);
20330 if (processing_template_decl)
20331 /* Try again at instantiation time. */
20333 if (type && type != error_mark_node)
20334 /* If type is error_mark_node a diagnostic must have been
20335 emitted by now. Also, having a mention to '<type error>'
20336 in the diagnostic is not really useful to the user. */
20337 error ("unable to deduce %qT from %qE", type, init);
20338 return error_mark_node;
20341 /* If the list of declarators contains more than one declarator, the type
20342 of each declared variable is determined as described above. If the
20343 type deduced for the template parameter U is not the same in each
20344 deduction, the program is ill-formed. */
20345 if (TREE_TYPE (auto_node)
20346 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
20348 error ("inconsistent deduction for %qT: %qT and then %qT",
20349 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
20350 return error_mark_node;
20352 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
20354 if (processing_template_decl)
20355 targs = add_to_template_args (current_template_args (), targs);
20356 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
20359 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
20363 splice_late_return_type (tree type, tree late_return_type)
20367 if (late_return_type == NULL_TREE)
20369 argvec = make_tree_vec (1);
20370 TREE_VEC_ELT (argvec, 0) = late_return_type;
20371 if (processing_template_parmlist)
20372 /* For a late-specified return type in a template type-parameter, we
20373 need to add a dummy argument level for its parmlist. */
20374 argvec = add_to_template_args
20375 (make_tree_vec (processing_template_parmlist), argvec);
20376 if (current_template_parms)
20377 argvec = add_to_template_args (current_template_args (), argvec);
20378 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20381 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
20384 is_auto (const_tree type)
20386 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
20387 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
20393 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
20394 appear as a type-specifier for the declaration in question, we don't
20395 have to look through the whole type. */
20398 type_uses_auto (tree type)
20400 enum tree_code code;
20401 if (is_auto (type))
20404 code = TREE_CODE (type);
20406 if (code == POINTER_TYPE || code == REFERENCE_TYPE
20407 || code == OFFSET_TYPE || code == FUNCTION_TYPE
20408 || code == METHOD_TYPE || code == ARRAY_TYPE)
20409 return type_uses_auto (TREE_TYPE (type));
20411 if (TYPE_PTRMEMFUNC_P (type))
20412 return type_uses_auto (TREE_TYPE (TREE_TYPE
20413 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
20418 /* For a given template T, return the vector of typedefs referenced
20419 in T for which access check is needed at T instantiation time.
20420 T is either a FUNCTION_DECL or a RECORD_TYPE.
20421 Those typedefs were added to T by the function
20422 append_type_to_template_for_access_check. */
20424 VEC(qualified_typedef_usage_t,gc)*
20425 get_types_needing_access_check (tree t)
20428 VEC(qualified_typedef_usage_t,gc) *result = NULL;
20430 if (!t || t == error_mark_node)
20433 if (!(ti = get_template_info (t)))
20436 if (CLASS_TYPE_P (t)
20437 || TREE_CODE (t) == FUNCTION_DECL)
20439 if (!TI_TEMPLATE (ti))
20442 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
20448 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
20449 tied to T. That list of typedefs will be access checked at
20450 T instantiation time.
20451 T is either a FUNCTION_DECL or a RECORD_TYPE.
20452 TYPE_DECL is a TYPE_DECL node representing a typedef.
20453 SCOPE is the scope through which TYPE_DECL is accessed.
20454 LOCATION is the location of the usage point of TYPE_DECL.
20456 This function is a subroutine of
20457 append_type_to_template_for_access_check. */
20460 append_type_to_template_for_access_check_1 (tree t,
20463 location_t location)
20465 qualified_typedef_usage_t typedef_usage;
20468 if (!t || t == error_mark_node)
20471 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
20472 || CLASS_TYPE_P (t))
20474 && TREE_CODE (type_decl) == TYPE_DECL
20477 if (!(ti = get_template_info (t)))
20480 gcc_assert (TI_TEMPLATE (ti));
20482 typedef_usage.typedef_decl = type_decl;
20483 typedef_usage.context = scope;
20484 typedef_usage.locus = location;
20486 VEC_safe_push (qualified_typedef_usage_t, gc,
20487 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
20491 /* Append TYPE_DECL to the template TEMPL.
20492 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
20493 At TEMPL instanciation time, TYPE_DECL will be checked to see
20494 if it can be accessed through SCOPE.
20495 LOCATION is the location of the usage point of TYPE_DECL.
20497 e.g. consider the following code snippet:
20504 template<class U> struct S
20506 C::myint mi; // <-- usage point of the typedef C::myint
20511 At S<char> instantiation time, we need to check the access of C::myint
20512 In other words, we need to check the access of the myint typedef through
20513 the C scope. For that purpose, this function will add the myint typedef
20514 and the scope C through which its being accessed to a list of typedefs
20515 tied to the template S. That list will be walked at template instantiation
20516 time and access check performed on each typedefs it contains.
20517 Note that this particular code snippet should yield an error because
20518 myint is private to C. */
20521 append_type_to_template_for_access_check (tree templ,
20524 location_t location)
20526 qualified_typedef_usage_t *iter;
20529 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
20531 /* Make sure we don't append the type to the template twice. */
20532 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
20533 get_types_needing_access_check (templ),
20535 if (iter->typedef_decl == type_decl && scope == iter->context)
20538 append_type_to_template_for_access_check_1 (templ, type_decl,
20542 /* Set up the hash tables for template instantiations. */
20545 init_template_processing (void)
20547 decl_specializations = htab_create_ggc (37,
20548 hash_specialization,
20549 eq_specializations,
20551 type_specializations = htab_create_ggc (37,
20552 hash_specialization,
20553 eq_specializations,
20557 /* Print stats about the template hash tables for -fstats. */
20560 print_template_statistics (void)
20562 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
20563 "%f collisions\n", (long) htab_size (decl_specializations),
20564 (long) htab_elements (decl_specializations),
20565 htab_collisions (decl_specializations));
20566 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
20567 "%f collisions\n", (long) htab_size (type_specializations),
20568 (long) htab_elements (type_specializations),
20569 htab_collisions (type_specializations));
20572 #include "gt-cp-pt.h"